/usr/lib/python3/dist-packages/sqlalchemy/dialects/postgresql/base.py is in python3-sqlalchemy 1.1.11+ds1-1ubuntu1.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 700 701 702 703 704 705 706 707 708 709 710 711 712 713 714 715 716 717 718 719 720 721 722 723 724 725 726 727 728 729 730 731 732 733 734 735 736 737 738 739 740 741 742 743 744 745 746 747 748 749 750 751 752 753 754 755 756 757 758 759 760 761 762 763 764 765 766 767 768 769 770 771 772 773 774 775 776 777 778 779 780 781 782 783 784 785 786 787 788 789 790 791 792 793 794 795 796 797 798 799 800 801 802 803 804 805 806 807 808 809 810 811 812 813 814 815 816 817 818 819 820 821 822 823 824 825 826 827 828 829 830 831 832 833 834 835 836 837 838 839 840 841 842 843 844 845 846 847 848 849 850 851 852 853 854 855 856 857 858 859 860 861 862 863 864 865 866 867 868 869 870 871 872 873 874 875 876 877 878 879 880 881 882 883 884 885 886 887 888 889 890 891 892 893 894 895 896 897 898 899 900 901 902 903 904 905 906 907 908 909 910 911 912 913 914 915 916 917 918 919 920 921 922 923 924 925 926 927 928 929 930 931 932 933 934 935 936 937 938 939 940 941 942 943 944 945 946 947 948 949 950 951 952 953 954 955 956 957 958 959 960 961 962 963 964 965 966 967 968 969 970 971 972 973 974 975 976 977 978 979 980 981 982 983 984 985 986 987 988 989 990 991 992 993 994 995 996 997 998 999 1000 1001 1002 1003 1004 1005 1006 1007 1008 1009 1010 1011 1012 1013 1014 1015 1016 1017 1018 1019 1020 1021 1022 1023 1024 1025 1026 1027 1028 1029 1030 1031 1032 1033 1034 1035 1036 1037 1038 1039 1040 1041 1042 1043 1044 1045 1046 1047 1048 1049 1050 1051 1052 1053 1054 1055 1056 1057 1058 1059 1060 1061 1062 1063 1064 1065 1066 1067 1068 1069 1070 1071 1072 1073 1074 1075 1076 1077 1078 1079 1080 1081 1082 1083 1084 1085 1086 1087 1088 1089 1090 1091 1092 1093 1094 1095 1096 1097 1098 1099 1100 1101 1102 1103 1104 1105 1106 1107 1108 1109 1110 1111 1112 1113 1114 1115 1116 1117 1118 1119 1120 1121 1122 1123 1124 1125 1126 1127 1128 1129 1130 1131 1132 1133 1134 1135 1136 1137 1138 1139 1140 1141 1142 1143 1144 1145 1146 1147 1148 1149 1150 1151 1152 1153 1154 1155 1156 1157 1158 1159 1160 1161 1162 1163 1164 1165 1166 1167 1168 1169 1170 1171 1172 1173 1174 1175 1176 1177 1178 1179 1180 1181 1182 1183 1184 1185 1186 1187 1188 1189 1190 1191 1192 1193 1194 1195 1196 1197 1198 1199 1200 1201 1202 1203 1204 1205 1206 1207 1208 1209 1210 1211 1212 1213 1214 1215 1216 1217 1218 1219 1220 1221 1222 1223 1224 1225 1226 1227 1228 1229 1230 1231 1232 1233 1234 1235 1236 1237 1238 1239 1240 1241 1242 1243 1244 1245 1246 1247 1248 1249 1250 1251 1252 1253 1254 1255 1256 1257 1258 1259 1260 1261 1262 1263 1264 1265 1266 1267 1268 1269 1270 1271 1272 1273 1274 1275 1276 1277 1278 1279 1280 1281 1282 1283 1284 1285 1286 1287 1288 1289 1290 1291 1292 1293 1294 1295 1296 1297 1298 1299 1300 1301 1302 1303 1304 1305 1306 1307 1308 1309 1310 1311 1312 1313 1314 1315 1316 1317 1318 1319 1320 1321 1322 1323 1324 1325 1326 1327 1328 1329 1330 1331 1332 1333 1334 1335 1336 1337 1338 1339 1340 1341 1342 1343 1344 1345 1346 1347 1348 1349 1350 1351 1352 1353 1354 1355 1356 1357 1358 1359 1360 1361 1362 1363 1364 1365 1366 1367 1368 1369 1370 1371 1372 1373 1374 1375 1376 1377 1378 1379 1380 1381 1382 1383 1384 1385 1386 1387 1388 1389 1390 1391 1392 1393 1394 1395 1396 1397 1398 1399 1400 1401 1402 1403 1404 1405 1406 1407 1408 1409 1410 1411 1412 1413 1414 1415 1416 1417 1418 1419 1420 1421 1422 1423 1424 1425 1426 1427 1428 1429 1430 1431 1432 1433 1434 1435 1436 1437 1438 1439 1440 1441 1442 1443 1444 1445 1446 1447 1448 1449 1450 1451 1452 1453 1454 1455 1456 1457 1458 1459 1460 1461 1462 1463 1464 1465 1466 1467 1468 1469 1470 1471 1472 1473 1474 1475 1476 1477 1478 1479 1480 1481 1482 1483 1484 1485 1486 1487 1488 1489 1490 1491 1492 1493 1494 1495 1496 1497 1498 1499 1500 1501 1502 1503 1504 1505 1506 1507 1508 1509 1510 1511 1512 1513 1514 1515 1516 1517 1518 1519 1520 1521 1522 1523 1524 1525 1526 1527 1528 1529 1530 1531 1532 1533 1534 1535 1536 1537 1538 1539 1540 1541 1542 1543 1544 1545 1546 1547 1548 1549 1550 1551 1552 1553 1554 1555 1556 1557 1558 1559 1560 1561 1562 1563 1564 1565 1566 1567 1568 1569 1570 1571 1572 1573 1574 1575 1576 1577 1578 1579 1580 1581 1582 1583 1584 1585 1586 1587 1588 1589 1590 1591 1592 1593 1594 1595 1596 1597 1598 1599 1600 1601 1602 1603 1604 1605 1606 1607 1608 1609 1610 1611 1612 1613 1614 1615 1616 1617 1618 1619 1620 1621 1622 1623 1624 1625 1626 1627 1628 1629 1630 1631 1632 1633 1634 1635 1636 1637 1638 1639 1640 1641 1642 1643 1644 1645 1646 1647 1648 1649 1650 1651 1652 1653 1654 1655 1656 1657 1658 1659 1660 1661 1662 1663 1664 1665 1666 1667 1668 1669 1670 1671 1672 1673 1674 1675 1676 1677 1678 1679 1680 1681 1682 1683 1684 1685 1686 1687 1688 1689 1690 1691 1692 1693 1694 1695 1696 1697 1698 1699 1700 1701 1702 1703 1704 1705 1706 1707 1708 1709 1710 1711 1712 1713 1714 1715 1716 1717 1718 1719 1720 1721 1722 1723 1724 1725 1726 1727 1728 1729 1730 1731 1732 1733 1734 1735 1736 1737 1738 1739 1740 1741 1742 1743 1744 1745 1746 1747 1748 1749 1750 1751 1752 1753 1754 1755 1756 1757 1758 1759 1760 1761 1762 1763 1764 1765 1766 1767 1768 1769 1770 1771 1772 1773 1774 1775 1776 1777 1778 1779 1780 1781 1782 1783 1784 1785 1786 1787 1788 1789 1790 1791 1792 1793 1794 1795 1796 1797 1798 1799 1800 1801 1802 1803 1804 1805 1806 1807 1808 1809 1810 1811 1812 1813 1814 1815 1816 1817 1818 1819 1820 1821 1822 1823 1824 1825 1826 1827 1828 1829 1830 1831 1832 1833 1834 1835 1836 1837 1838 1839 1840 1841 1842 1843 1844 1845 1846 1847 1848 1849 1850 1851 1852 1853 1854 1855 1856 1857 1858 1859 1860 1861 1862 1863 1864 1865 1866 1867 1868 1869 1870 1871 1872 1873 1874 1875 1876 1877 1878 1879 1880 1881 1882 1883 1884 1885 1886 1887 1888 1889 1890 1891 1892 1893 1894 1895 1896 1897 1898 1899 1900 1901 1902 1903 1904 1905 1906 1907 1908 1909 1910 1911 1912 1913 1914 1915 1916 1917 1918 1919 1920 1921 1922 1923 1924 1925 1926 1927 1928 1929 1930 1931 1932 1933 1934 1935 1936 1937 1938 1939 1940 1941 1942 1943 1944 1945 1946 1947 1948 1949 1950 1951 1952 1953 1954 1955 1956 1957 1958 1959 1960 1961 1962 1963 1964 1965 1966 1967 1968 1969 1970 1971 1972 1973 1974 1975 1976 1977 1978 1979 1980 1981 1982 1983 1984 1985 1986 1987 1988 1989 1990 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 2022 2023 2024 2025 2026 2027 2028 2029 2030 2031 2032 2033 2034 2035 2036 2037 2038 2039 2040 2041 2042 2043 2044 2045 2046 2047 2048 2049 2050 2051 2052 2053 2054 2055 2056 2057 2058 2059 2060 2061 2062 2063 2064 2065 2066 2067 2068 2069 2070 2071 2072 2073 2074 2075 2076 2077 2078 2079 2080 2081 2082 2083 2084 2085 2086 2087 2088 2089 2090 2091 2092 2093 2094 2095 2096 2097 2098 2099 2100 2101 2102 2103 2104 2105 2106 2107 2108 2109 2110 2111 2112 2113 2114 2115 2116 2117 2118 2119 2120 2121 2122 2123 2124 2125 2126 2127 2128 2129 2130 2131 2132 2133 2134 2135 2136 2137 2138 2139 2140 2141 2142 2143 2144 2145 2146 2147 2148 2149 2150 2151 2152 2153 2154 2155 2156 2157 2158 2159 2160 2161 2162 2163 2164 2165 2166 2167 2168 2169 2170 2171 2172 2173 2174 2175 2176 2177 2178 2179 2180 2181 2182 2183 2184 2185 2186 2187 2188 2189 2190 2191 2192 2193 2194 2195 2196 2197 2198 2199 2200 2201 2202 2203 2204 2205 2206 2207 2208 2209 2210 2211 2212 2213 2214 2215 2216 2217 2218 2219 2220 2221 2222 2223 2224 2225 2226 2227 2228 2229 2230 2231 2232 2233 2234 2235 2236 2237 2238 2239 2240 2241 2242 2243 2244 2245 2246 2247 2248 2249 2250 2251 2252 2253 2254 2255 2256 2257 2258 2259 2260 2261 2262 2263 2264 2265 2266 2267 2268 2269 2270 2271 2272 2273 2274 2275 2276 2277 2278 2279 2280 2281 2282 2283 2284 2285 2286 2287 2288 2289 2290 2291 2292 2293 2294 2295 2296 2297 2298 2299 2300 2301 2302 2303 2304 2305 2306 2307 2308 2309 2310 2311 2312 2313 2314 2315 2316 2317 2318 2319 2320 2321 2322 2323 2324 2325 2326 2327 2328 2329 2330 2331 2332 2333 2334 2335 2336 2337 2338 2339 2340 2341 2342 2343 2344 2345 2346 2347 2348 2349 2350 2351 2352 2353 2354 2355 2356 2357 2358 2359 2360 2361 2362 2363 2364 2365 2366 2367 2368 2369 2370 2371 2372 2373 2374 2375 2376 2377 2378 2379 2380 2381 2382 2383 2384 2385 2386 2387 2388 2389 2390 2391 2392 2393 2394 2395 2396 2397 2398 2399 2400 2401 2402 2403 2404 2405 2406 2407 2408 2409 2410 2411 2412 2413 2414 2415 2416 2417 2418 2419 2420 2421 2422 2423 2424 2425 2426 2427 2428 2429 2430 2431 2432 2433 2434 2435 2436 2437 2438 2439 2440 2441 2442 2443 2444 2445 2446 2447 2448 2449 2450 2451 2452 2453 2454 2455 2456 2457 2458 2459 2460 2461 2462 2463 2464 2465 2466 2467 2468 2469 2470 2471 2472 2473 2474 2475 2476 2477 2478 2479 2480 2481 2482 2483 2484 2485 2486 2487 2488 2489 2490 2491 2492 2493 2494 2495 2496 2497 2498 2499 2500 2501 2502 2503 2504 2505 2506 2507 2508 2509 2510 2511 2512 2513 2514 2515 2516 2517 2518 2519 2520 2521 2522 2523 2524 2525 2526 2527 2528 2529 2530 2531 2532 2533 2534 2535 2536 2537 2538 2539 2540 2541 2542 2543 2544 2545 2546 2547 2548 2549 2550 2551 2552 2553 2554 2555 2556 2557 2558 2559 2560 2561 2562 2563 2564 2565 2566 2567 2568 2569 2570 2571 2572 2573 2574 2575 2576 2577 2578 2579 2580 2581 2582 2583 2584 2585 2586 2587 2588 2589 2590 2591 2592 2593 2594 2595 2596 2597 2598 2599 2600 2601 2602 2603 2604 2605 2606 2607 2608 2609 2610 2611 2612 2613 2614 2615 2616 2617 2618 2619 2620 2621 2622 2623 2624 2625 2626 2627 2628 2629 2630 2631 2632 2633 2634 2635 2636 2637 2638 2639 2640 2641 2642 2643 2644 2645 2646 2647 2648 2649 2650 2651 2652 2653 2654 2655 2656 2657 2658 2659 2660 2661 2662 2663 2664 2665 2666 2667 2668 2669 2670 2671 2672 2673 2674 2675 2676 2677 2678 2679 2680 2681 2682 2683 2684 2685 2686 2687 2688 2689 2690 2691 2692 2693 2694 2695 2696 2697 2698 2699 2700 2701 2702 2703 2704 2705 2706 2707 2708 2709 2710 2711 2712 2713 2714 2715 2716 2717 2718 2719 2720 2721 2722 2723 2724 2725 2726 2727 2728 2729 2730 2731 2732 2733 2734 2735 2736 2737 2738 2739 2740 2741 2742 2743 2744 2745 2746 2747 2748 2749 2750 2751 2752 2753 2754 2755 2756 2757 2758 2759 2760 2761 2762 2763 2764 2765 2766 2767 2768 2769 2770 2771 2772 2773 2774 2775 2776 2777 2778 2779 2780 2781 2782 2783 2784 2785 2786 2787 2788 2789 2790 2791 2792 2793 2794 2795 2796 2797 2798 2799 2800 2801 2802 2803 2804 2805 2806 2807 2808 2809 2810 2811 2812 2813 2814 2815 2816 2817 2818 2819 2820 2821 2822 2823 2824 2825 2826 2827 2828 2829 2830 2831 2832 2833 2834 2835 2836 2837 2838 2839 2840 2841 2842 2843 2844 2845 2846 2847 2848 2849 2850 2851 2852 2853 2854 2855 2856 2857 2858 2859 2860 2861 2862 2863 2864 2865 2866 2867 2868 2869 2870 2871 2872 2873 2874 2875 2876 2877 2878 2879 2880 2881 2882 2883 2884 2885 2886 2887 2888 2889 2890 2891 2892 2893 2894 2895 2896 2897 2898 2899 2900 2901 2902 2903 2904 2905 2906 2907 2908 2909 2910 2911 2912 2913 2914 2915 2916 2917 2918 2919 2920 2921 2922 2923 2924 2925 2926 2927 2928 2929 2930 2931 2932 2933 2934 2935 2936 2937 2938 2939 2940 2941 2942 2943 2944 2945 2946 2947 2948 2949 2950 2951 2952 2953 2954 2955 2956 2957 2958 2959 2960 2961 2962 2963 2964 2965 2966 2967 2968 2969 2970 2971 2972 2973 2974 2975 2976 2977 2978 2979 2980 2981 2982 2983 2984 2985 2986 2987 2988 2989 2990 2991 2992 2993 2994 2995 2996 2997 2998 2999 3000 3001 3002 3003 3004 3005 3006 | # postgresql/base.py
# Copyright (C) 2005-2017 the SQLAlchemy authors and contributors
# <see AUTHORS file>
#
# This module is part of SQLAlchemy and is released under
# the MIT License: http://www.opensource.org/licenses/mit-license.php
r"""
.. dialect:: postgresql
:name: PostgreSQL
.. _postgresql_sequences:
Sequences/SERIAL
----------------
PostgreSQL supports sequences, and SQLAlchemy uses these as the default means
of creating new primary key values for integer-based primary key columns. When
creating tables, SQLAlchemy will issue the ``SERIAL`` datatype for
integer-based primary key columns, which generates a sequence and server side
default corresponding to the column.
To specify a specific named sequence to be used for primary key generation,
use the :func:`~sqlalchemy.schema.Sequence` construct::
Table('sometable', metadata,
Column('id', Integer, Sequence('some_id_seq'), primary_key=True)
)
When SQLAlchemy issues a single INSERT statement, to fulfill the contract of
having the "last insert identifier" available, a RETURNING clause is added to
the INSERT statement which specifies the primary key columns should be
returned after the statement completes. The RETURNING functionality only takes
place if PostgreSQL 8.2 or later is in use. As a fallback approach, the
sequence, whether specified explicitly or implicitly via ``SERIAL``, is
executed independently beforehand, the returned value to be used in the
subsequent insert. Note that when an
:func:`~sqlalchemy.sql.expression.insert()` construct is executed using
"executemany" semantics, the "last inserted identifier" functionality does not
apply; no RETURNING clause is emitted nor is the sequence pre-executed in this
case.
To force the usage of RETURNING by default off, specify the flag
``implicit_returning=False`` to :func:`.create_engine`.
.. _postgresql_isolation_level:
Transaction Isolation Level
---------------------------
All PostgreSQL dialects support setting of transaction isolation level
both via a dialect-specific parameter
:paramref:`.create_engine.isolation_level` accepted by :func:`.create_engine`,
as well as the :paramref:`.Connection.execution_options.isolation_level`
argument as passed to :meth:`.Connection.execution_options`.
When using a non-psycopg2 dialect, this feature works by issuing the command
``SET SESSION CHARACTERISTICS AS TRANSACTION ISOLATION LEVEL <level>`` for
each new connection. For the special AUTOCOMMIT isolation level,
DBAPI-specific techniques are used.
To set isolation level using :func:`.create_engine`::
engine = create_engine(
"postgresql+pg8000://scott:tiger@localhost/test",
isolation_level="READ UNCOMMITTED"
)
To set using per-connection execution options::
connection = engine.connect()
connection = connection.execution_options(
isolation_level="READ COMMITTED"
)
Valid values for ``isolation_level`` include:
* ``READ COMMITTED``
* ``READ UNCOMMITTED``
* ``REPEATABLE READ``
* ``SERIALIZABLE``
* ``AUTOCOMMIT`` - on psycopg2 / pg8000 only
.. seealso::
:ref:`psycopg2_isolation_level`
:ref:`pg8000_isolation_level`
.. _postgresql_schema_reflection:
Remote-Schema Table Introspection and PostgreSQL search_path
------------------------------------------------------------
The PostgreSQL dialect can reflect tables from any schema. The
:paramref:`.Table.schema` argument, or alternatively the
:paramref:`.MetaData.reflect.schema` argument determines which schema will
be searched for the table or tables. The reflected :class:`.Table` objects
will in all cases retain this ``.schema`` attribute as was specified.
However, with regards to tables which these :class:`.Table` objects refer to
via foreign key constraint, a decision must be made as to how the ``.schema``
is represented in those remote tables, in the case where that remote
schema name is also a member of the current
`PostgreSQL search path
<http://www.postgresql.org/docs/current/static/ddl-schemas.html#DDL-SCHEMAS-PATH>`_.
By default, the PostgreSQL dialect mimics the behavior encouraged by
PostgreSQL's own ``pg_get_constraintdef()`` builtin procedure. This function
returns a sample definition for a particular foreign key constraint,
omitting the referenced schema name from that definition when the name is
also in the PostgreSQL schema search path. The interaction below
illustrates this behavior::
test=> CREATE TABLE test_schema.referred(id INTEGER PRIMARY KEY);
CREATE TABLE
test=> CREATE TABLE referring(
test(> id INTEGER PRIMARY KEY,
test(> referred_id INTEGER REFERENCES test_schema.referred(id));
CREATE TABLE
test=> SET search_path TO public, test_schema;
test=> SELECT pg_catalog.pg_get_constraintdef(r.oid, true) FROM
test-> pg_catalog.pg_class c JOIN pg_catalog.pg_namespace n
test-> ON n.oid = c.relnamespace
test-> JOIN pg_catalog.pg_constraint r ON c.oid = r.conrelid
test-> WHERE c.relname='referring' AND r.contype = 'f'
test-> ;
pg_get_constraintdef
---------------------------------------------------
FOREIGN KEY (referred_id) REFERENCES referred(id)
(1 row)
Above, we created a table ``referred`` as a member of the remote schema
``test_schema``, however when we added ``test_schema`` to the
PG ``search_path`` and then asked ``pg_get_constraintdef()`` for the
``FOREIGN KEY`` syntax, ``test_schema`` was not included in the output of
the function.
On the other hand, if we set the search path back to the typical default
of ``public``::
test=> SET search_path TO public;
SET
The same query against ``pg_get_constraintdef()`` now returns the fully
schema-qualified name for us::
test=> SELECT pg_catalog.pg_get_constraintdef(r.oid, true) FROM
test-> pg_catalog.pg_class c JOIN pg_catalog.pg_namespace n
test-> ON n.oid = c.relnamespace
test-> JOIN pg_catalog.pg_constraint r ON c.oid = r.conrelid
test-> WHERE c.relname='referring' AND r.contype = 'f';
pg_get_constraintdef
---------------------------------------------------------------
FOREIGN KEY (referred_id) REFERENCES test_schema.referred(id)
(1 row)
SQLAlchemy will by default use the return value of ``pg_get_constraintdef()``
in order to determine the remote schema name. That is, if our ``search_path``
were set to include ``test_schema``, and we invoked a table
reflection process as follows::
>>> from sqlalchemy import Table, MetaData, create_engine
>>> engine = create_engine("postgresql://scott:tiger@localhost/test")
>>> with engine.connect() as conn:
... conn.execute("SET search_path TO test_schema, public")
... meta = MetaData()
... referring = Table('referring', meta,
... autoload=True, autoload_with=conn)
...
<sqlalchemy.engine.result.ResultProxy object at 0x101612ed0>
The above process would deliver to the :attr:`.MetaData.tables` collection
``referred`` table named **without** the schema::
>>> meta.tables['referred'].schema is None
True
To alter the behavior of reflection such that the referred schema is
maintained regardless of the ``search_path`` setting, use the
``postgresql_ignore_search_path`` option, which can be specified as a
dialect-specific argument to both :class:`.Table` as well as
:meth:`.MetaData.reflect`::
>>> with engine.connect() as conn:
... conn.execute("SET search_path TO test_schema, public")
... meta = MetaData()
... referring = Table('referring', meta, autoload=True,
... autoload_with=conn,
... postgresql_ignore_search_path=True)
...
<sqlalchemy.engine.result.ResultProxy object at 0x1016126d0>
We will now have ``test_schema.referred`` stored as schema-qualified::
>>> meta.tables['test_schema.referred'].schema
'test_schema'
.. sidebar:: Best Practices for PostgreSQL Schema reflection
The description of PostgreSQL schema reflection behavior is complex, and
is the product of many years of dealing with widely varied use cases and
user preferences. But in fact, there's no need to understand any of it if
you just stick to the simplest use pattern: leave the ``search_path`` set
to its default of ``public`` only, never refer to the name ``public`` as
an explicit schema name otherwise, and refer to all other schema names
explicitly when building up a :class:`.Table` object. The options
described here are only for those users who can't, or prefer not to, stay
within these guidelines.
Note that **in all cases**, the "default" schema is always reflected as
``None``. The "default" schema on PostgreSQL is that which is returned by the
PostgreSQL ``current_schema()`` function. On a typical PostgreSQL
installation, this is the name ``public``. So a table that refers to another
which is in the ``public`` (i.e. default) schema will always have the
``.schema`` attribute set to ``None``.
.. versionadded:: 0.9.2 Added the ``postgresql_ignore_search_path``
dialect-level option accepted by :class:`.Table` and
:meth:`.MetaData.reflect`.
.. seealso::
`The Schema Search Path
<http://www.postgresql.org/docs/9.0/static/ddl-schemas.html#DDL-SCHEMAS-PATH>`_
- on the PostgreSQL website.
INSERT/UPDATE...RETURNING
-------------------------
The dialect supports PG 8.2's ``INSERT..RETURNING``, ``UPDATE..RETURNING`` and
``DELETE..RETURNING`` syntaxes. ``INSERT..RETURNING`` is used by default
for single-row INSERT statements in order to fetch newly generated
primary key identifiers. To specify an explicit ``RETURNING`` clause,
use the :meth:`._UpdateBase.returning` method on a per-statement basis::
# INSERT..RETURNING
result = table.insert().returning(table.c.col1, table.c.col2).\
values(name='foo')
print result.fetchall()
# UPDATE..RETURNING
result = table.update().returning(table.c.col1, table.c.col2).\
where(table.c.name=='foo').values(name='bar')
print result.fetchall()
# DELETE..RETURNING
result = table.delete().returning(table.c.col1, table.c.col2).\
where(table.c.name=='foo')
print result.fetchall()
.. _postgresql_insert_on_conflict:
INSERT...ON CONFLICT (Upsert)
------------------------------
Starting with version 9.5, PostgreSQL allows "upserts" (update or insert)
of rows into a table via the ``ON CONFLICT`` clause of the ``INSERT`` statement.
A candidate row will only be inserted if that row does not violate
any unique constraints. In the case of a unique constraint violation,
a secondary action can occur which can be either "DO UPDATE", indicating
that the data in the target row should be updated, or "DO NOTHING",
which indicates to silently skip this row.
Conflicts are determined using existing unique constraints and indexes. These
constraints may be identified either using their name as stated in DDL,
or they may be *inferred* by stating the columns and conditions that comprise
the indexes.
SQLAlchemy provides ``ON CONFLICT`` support via the PostgreSQL-specific
:func:`.postgresql.dml.insert()` function, which provides
the generative methods :meth:`~.postgresql.dml.Insert.on_conflict_do_update`
and :meth:`~.postgresql.dml.Insert.on_conflict_do_nothing`::
from sqlalchemy.dialects.postgresql import insert
insert_stmt = insert(my_table).values(
id='some_existing_id',
data='inserted value')
do_nothing_stmt = insert_stmt.on_conflict_do_nothing(
index_elements=['id']
)
conn.execute(do_nothing_stmt)
do_update_stmt = insert_stmt.on_conflict_do_update(
constraint='pk_my_table',
set_=dict(data='updated value')
)
conn.execute(do_update_stmt)
Both methods supply the "target" of the conflict using either the
named constraint or by column inference:
* The :paramref:`.Insert.on_conflict_do_update.index_elements` argument
specifies a sequence containing string column names, :class:`.Column` objects,
and/or SQL expression elements, which would identify a unique index::
do_update_stmt = insert_stmt.on_conflict_do_update(
index_elements=['id'],
set_=dict(data='updated value')
)
do_update_stmt = insert_stmt.on_conflict_do_update(
index_elements=[my_table.c.id],
set_=dict(data='updated value')
)
* When using :paramref:`.Insert.on_conflict_do_update.index_elements` to
infer an index, a partial index can be inferred by also specifying the
use the :paramref:`.Insert.on_conflict_do_update.index_where` parameter::
from sqlalchemy.dialects.postgresql import insert
stmt = insert(my_table).values(user_email='a@b.com', data='inserted data')
stmt = stmt.on_conflict_do_update(
index_elements=[my_table.c.user_email],
index_where=my_table.c.user_email.like('%@gmail.com'),
set_=dict(data=stmt.excluded.data)
)
conn.execute(stmt)
* The :paramref:`.Insert.on_conflict_do_update.constraint` argument is
used to specify an index directly rather than inferring it. This can be
the name of a UNIQUE constraint, a PRIMARY KEY constraint, or an INDEX::
do_update_stmt = insert_stmt.on_conflict_do_update(
constraint='my_table_idx_1',
set_=dict(data='updated value')
)
do_update_stmt = insert_stmt.on_conflict_do_update(
constraint='my_table_pk',
set_=dict(data='updated value')
)
* The :paramref:`.Insert.on_conflict_do_update.constraint` argument may
also refer to a SQLAlchemy construct representing a constraint,
e.g. :class:`.UniqueConstraint`, :class:`.PrimaryKeyConstraint`,
:class:`.Index`, or :class:`.ExcludeConstraint`. In this use,
if the constraint has a name, it is used directly. Otherwise, if the
constraint is unnamed, then inference will be used, where the expressions
and optional WHERE clause of the constraint will be spelled out in the
construct. This use is especially convenient
to refer to the named or unnamed primary key of a :class:`.Table` using the
:attr:`.Table.primary_key` attribute::
do_update_stmt = insert_stmt.on_conflict_do_update(
constraint=my_table.primary_key,
set_=dict(data='updated value')
)
``ON CONFLICT...DO UPDATE`` is used to perform an update of the already
existing row, using any combination of new values as well as values
from the proposed insertion. These values are specified using the
:paramref:`.Insert.on_conflict_do_update.set_` parameter. This
parameter accepts a dictionary which consists of direct values
for UPDATE::
from sqlalchemy.dialects.postgresql import insert
stmt = insert(my_table).values(id='some_id', data='inserted value')
do_update_stmt = stmt.on_conflict_do_update(
index_elements=['id'],
set_=dict(data='updated value')
)
conn.execute(do_update_stmt)
.. warning::
The :meth:`.Insert.on_conflict_do_update` method does **not** take into
account Python-side default UPDATE values or generation functions, e.g.
e.g. those specified using :paramref:`.Column.onupdate`.
These values will not be exercised for an ON CONFLICT style of UPDATE,
unless they are manually specified in the
:paramref:`.Insert.on_conflict_do_update.set_` dictionary.
In order to refer to the proposed insertion row, the special alias
:attr:`~.postgresql.dml.Insert.excluded` is available as an attribute on
the :class:`.postgresql.dml.Insert` object; this object is a
:class:`.ColumnCollection` which alias contains all columns of the target
table::
from sqlalchemy.dialects.postgresql import insert
stmt = insert(my_table).values(
id='some_id',
data='inserted value',
author='jlh')
do_update_stmt = stmt.on_conflict_do_update(
index_elements=['id'],
set_=dict(data='updated value', author=stmt.excluded.author)
)
conn.execute(do_update_stmt)
The :meth:`.Insert.on_conflict_do_update` method also accepts
a WHERE clause using the :paramref:`.Insert.on_conflict_do_update.where`
parameter, which will limit those rows which receive an UPDATE::
from sqlalchemy.dialects.postgresql import insert
stmt = insert(my_table).values(
id='some_id',
data='inserted value',
author='jlh')
on_update_stmt = stmt.on_conflict_do_update(
index_elements=['id'],
set_=dict(data='updated value', author=stmt.excluded.author)
where=(my_table.c.status == 2)
)
conn.execute(on_update_stmt)
``ON CONFLICT`` may also be used to skip inserting a row entirely
if any conflict with a unique or exclusion constraint occurs; below
this is illustrated using the
:meth:`~.postgresql.dml.Insert.on_conflict_do_nothing` method::
from sqlalchemy.dialects.postgresql import insert
stmt = insert(my_table).values(id='some_id', data='inserted value')
stmt = stmt.on_conflict_do_nothing(index_elements=['id'])
conn.execute(stmt)
If ``DO NOTHING`` is used without specifying any columns or constraint,
it has the effect of skipping the INSERT for any unique or exclusion
constraint violation which occurs::
from sqlalchemy.dialects.postgresql import insert
stmt = insert(my_table).values(id='some_id', data='inserted value')
stmt = stmt.on_conflict_do_nothing()
conn.execute(stmt)
.. versionadded:: 1.1 Added support for PostgreSQL ON CONFLICT clauses
.. seealso::
`INSERT .. ON CONFLICT <http://www.postgresql.org/docs/current/static/sql-insert.html#SQL-ON-CONFLICT>`_ - in the PostgreSQL documentation.
.. _postgresql_match:
Full Text Search
----------------
SQLAlchemy makes available the PostgreSQL ``@@`` operator via the
:meth:`.ColumnElement.match` method on any textual column expression.
On a PostgreSQL dialect, an expression like the following::
select([sometable.c.text.match("search string")])
will emit to the database::
SELECT text @@ to_tsquery('search string') FROM table
The PostgreSQL text search functions such as ``to_tsquery()``
and ``to_tsvector()`` are available
explicitly using the standard :data:`.func` construct. For example::
select([
func.to_tsvector('fat cats ate rats').match('cat & rat')
])
Emits the equivalent of::
SELECT to_tsvector('fat cats ate rats') @@ to_tsquery('cat & rat')
The :class:`.postgresql.TSVECTOR` type can provide for explicit CAST::
from sqlalchemy.dialects.postgresql import TSVECTOR
from sqlalchemy import select, cast
select([cast("some text", TSVECTOR)])
produces a statement equivalent to::
SELECT CAST('some text' AS TSVECTOR) AS anon_1
Full Text Searches in PostgreSQL are influenced by a combination of: the
PostgresSQL setting of ``default_text_search_config``, the ``regconfig`` used
to build the GIN/GiST indexes, and the ``regconfig`` optionally passed in
during a query.
When performing a Full Text Search against a column that has a GIN or
GiST index that is already pre-computed (which is common on full text
searches) one may need to explicitly pass in a particular PostgresSQL
``regconfig`` value to ensure the query-planner utilizes the index and does
not re-compute the column on demand.
In order to provide for this explicit query planning, or to use different
search strategies, the ``match`` method accepts a ``postgresql_regconfig``
keyword argument::
select([mytable.c.id]).where(
mytable.c.title.match('somestring', postgresql_regconfig='english')
)
Emits the equivalent of::
SELECT mytable.id FROM mytable
WHERE mytable.title @@ to_tsquery('english', 'somestring')
One can also specifically pass in a `'regconfig'` value to the
``to_tsvector()`` command as the initial argument::
select([mytable.c.id]).where(
func.to_tsvector('english', mytable.c.title )\
.match('somestring', postgresql_regconfig='english')
)
produces a statement equivalent to::
SELECT mytable.id FROM mytable
WHERE to_tsvector('english', mytable.title) @@
to_tsquery('english', 'somestring')
It is recommended that you use the ``EXPLAIN ANALYZE...`` tool from
PostgresSQL to ensure that you are generating queries with SQLAlchemy that
take full advantage of any indexes you may have created for full text search.
FROM ONLY ...
------------------------
The dialect supports PostgreSQL's ONLY keyword for targeting only a particular
table in an inheritance hierarchy. This can be used to produce the
``SELECT ... FROM ONLY``, ``UPDATE ONLY ...``, and ``DELETE FROM ONLY ...``
syntaxes. It uses SQLAlchemy's hints mechanism::
# SELECT ... FROM ONLY ...
result = table.select().with_hint(table, 'ONLY', 'postgresql')
print result.fetchall()
# UPDATE ONLY ...
table.update(values=dict(foo='bar')).with_hint('ONLY',
dialect_name='postgresql')
# DELETE FROM ONLY ...
table.delete().with_hint('ONLY', dialect_name='postgresql')
.. _postgresql_indexes:
PostgreSQL-Specific Index Options
---------------------------------
Several extensions to the :class:`.Index` construct are available, specific
to the PostgreSQL dialect.
.. _postgresql_partial_indexes:
Partial Indexes
^^^^^^^^^^^^^^^^
Partial indexes add criterion to the index definition so that the index is
applied to a subset of rows. These can be specified on :class:`.Index`
using the ``postgresql_where`` keyword argument::
Index('my_index', my_table.c.id, postgresql_where=my_table.c.value > 10)
Operator Classes
^^^^^^^^^^^^^^^^^
PostgreSQL allows the specification of an *operator class* for each column of
an index (see
http://www.postgresql.org/docs/8.3/interactive/indexes-opclass.html).
The :class:`.Index` construct allows these to be specified via the
``postgresql_ops`` keyword argument::
Index(
'my_index', my_table.c.id, my_table.c.data,
postgresql_ops={
'data': 'text_pattern_ops',
'id': 'int4_ops'
})
Note that the keys in the ``postgresql_ops`` dictionary are the "key" name of
the :class:`.Column`, i.e. the name used to access it from the ``.c``
collection of :class:`.Table`, which can be configured to be different than
the actual name of the column as expressed in the database.
If ``postgresql_ops`` is to be used against a complex SQL expression such
as a function call, then to apply to the column it must be given a label
that is identified in the dictionary by name, e.g.::
Index(
'my_index', my_table.c.id,
func.lower(my_table.c.data).label('data_lower'),
postgresql_ops={
'data_lower': 'text_pattern_ops',
'id': 'int4_ops'
})
Index Types
^^^^^^^^^^^^
PostgreSQL provides several index types: B-Tree, Hash, GiST, and GIN, as well
as the ability for users to create their own (see
http://www.postgresql.org/docs/8.3/static/indexes-types.html). These can be
specified on :class:`.Index` using the ``postgresql_using`` keyword argument::
Index('my_index', my_table.c.data, postgresql_using='gin')
The value passed to the keyword argument will be simply passed through to the
underlying CREATE INDEX command, so it *must* be a valid index type for your
version of PostgreSQL.
.. _postgresql_index_storage:
Index Storage Parameters
^^^^^^^^^^^^^^^^^^^^^^^^
PostgreSQL allows storage parameters to be set on indexes. The storage
parameters available depend on the index method used by the index. Storage
parameters can be specified on :class:`.Index` using the ``postgresql_with``
keyword argument::
Index('my_index', my_table.c.data, postgresql_with={"fillfactor": 50})
.. versionadded:: 1.0.6
PostgreSQL allows to define the tablespace in which to create the index.
The tablespace can be specified on :class:`.Index` using the
``postgresql_tablespace`` keyword argument::
Index('my_index', my_table.c.data, postgresql_tablespace='my_tablespace')
.. versionadded:: 1.1
Note that the same option is available on :class:`.Table` as well.
.. _postgresql_index_concurrently:
Indexes with CONCURRENTLY
^^^^^^^^^^^^^^^^^^^^^^^^^
The PostgreSQL index option CONCURRENTLY is supported by passing the
flag ``postgresql_concurrently`` to the :class:`.Index` construct::
tbl = Table('testtbl', m, Column('data', Integer))
idx1 = Index('test_idx1', tbl.c.data, postgresql_concurrently=True)
The above index construct will render DDL for CREATE INDEX, assuming
PostgreSQL 8.2 or higher is detected or for a connection-less dialect, as::
CREATE INDEX CONCURRENTLY test_idx1 ON testtbl (data)
For DROP INDEX, assuming PostgreSQL 9.2 or higher is detected or for
a connection-less dialect, it will emit::
DROP INDEX CONCURRENTLY test_idx1
.. versionadded:: 1.1 support for CONCURRENTLY on DROP INDEX. The
CONCURRENTLY keyword is now only emitted if a high enough version
of PostgreSQL is detected on the connection (or for a connection-less
dialect).
When using CONCURRENTLY, the Postgresql database requires that the statement
be invoked outside of a transaction block. The Python DBAPI enforces that
even for a single statement, a transaction is present, so to use this
construct, the DBAPI's "autocommit" mode must be used::
metadata = MetaData()
table = Table(
"foo", metadata,
Column("id", String))
index = Index(
"foo_idx", table.c.id, postgresql_concurrently=True)
with engine.connect() as conn:
with conn.execution_options(isolation_level='AUTOCOMMIT'):
table.create(conn)
.. seealso::
:ref:`postgresql_isolation_level`
.. _postgresql_index_reflection:
PostgreSQL Index Reflection
---------------------------
The PostgreSQL database creates a UNIQUE INDEX implicitly whenever the
UNIQUE CONSTRAINT construct is used. When inspecting a table using
:class:`.Inspector`, the :meth:`.Inspector.get_indexes`
and the :meth:`.Inspector.get_unique_constraints` will report on these
two constructs distinctly; in the case of the index, the key
``duplicates_constraint`` will be present in the index entry if it is
detected as mirroring a constraint. When performing reflection using
``Table(..., autoload=True)``, the UNIQUE INDEX is **not** returned
in :attr:`.Table.indexes` when it is detected as mirroring a
:class:`.UniqueConstraint` in the :attr:`.Table.constraints` collection.
.. versionchanged:: 1.0.0 - :class:`.Table` reflection now includes
:class:`.UniqueConstraint` objects present in the :attr:`.Table.constraints`
collection; the PostgreSQL backend will no longer include a "mirrored"
:class:`.Index` construct in :attr:`.Table.indexes` if it is detected
as corresponding to a unique constraint.
Special Reflection Options
--------------------------
The :class:`.Inspector` used for the PostgreSQL backend is an instance
of :class:`.PGInspector`, which offers additional methods::
from sqlalchemy import create_engine, inspect
engine = create_engine("postgresql+psycopg2://localhost/test")
insp = inspect(engine) # will be a PGInspector
print(insp.get_enums())
.. autoclass:: PGInspector
:members:
.. _postgresql_table_options:
PostgreSQL Table Options
-------------------------
Several options for CREATE TABLE are supported directly by the PostgreSQL
dialect in conjunction with the :class:`.Table` construct:
* ``TABLESPACE``::
Table("some_table", metadata, ..., postgresql_tablespace='some_tablespace')
The above option is also available on the :class:`.Index` construct.
* ``ON COMMIT``::
Table("some_table", metadata, ..., postgresql_on_commit='PRESERVE ROWS')
* ``WITH OIDS``::
Table("some_table", metadata, ..., postgresql_with_oids=True)
* ``WITHOUT OIDS``::
Table("some_table", metadata, ..., postgresql_with_oids=False)
* ``INHERITS``::
Table("some_table", metadata, ..., postgresql_inherits="some_supertable")
Table("some_table", metadata, ..., postgresql_inherits=("t1", "t2", ...))
.. versionadded:: 1.0.0
.. seealso::
`PostgreSQL CREATE TABLE options
<http://www.postgresql.org/docs/current/static/sql-createtable.html>`_
ARRAY Types
-----------
The PostgreSQL dialect supports arrays, both as multidimensional column types
as well as array literals:
* :class:`.postgresql.ARRAY` - ARRAY datatype
* :class:`.postgresql.array` - array literal
* :func:`.postgresql.array_agg` - ARRAY_AGG SQL function
* :class:`.postgresql.aggregate_order_by` - helper for PG's ORDER BY aggregate
function syntax.
JSON Types
----------
The PostgreSQL dialect supports both JSON and JSONB datatypes, including
psycopg2's native support and support for all of PostgreSQL's special
operators:
* :class:`.postgresql.JSON`
* :class:`.postgresql.JSONB`
HSTORE Type
-----------
The PostgreSQL HSTORE type as well as hstore literals are supported:
* :class:`.postgresql.HSTORE` - HSTORE datatype
* :class:`.postgresql.hstore` - hstore literal
ENUM Types
----------
PostgreSQL has an independently creatable TYPE structure which is used
to implement an enumerated type. This approach introduces significant
complexity on the SQLAlchemy side in terms of when this type should be
CREATED and DROPPED. The type object is also an independently reflectable
entity. The following sections should be consulted:
* :class:`.postgresql.ENUM` - DDL and typing support for ENUM.
* :meth:`.PGInspector.get_enums` - retrieve a listing of current ENUM types
* :meth:`.postgresql.ENUM.create` , :meth:`.postgresql.ENUM.drop` - individual
CREATE and DROP commands for ENUM.
.. _postgresql_array_of_enum:
Using ENUM with ARRAY
^^^^^^^^^^^^^^^^^^^^^
The combination of ENUM and ARRAY is not directly supported by backend
DBAPIs at this time. In order to send and receive an ARRAY of ENUM,
use the following workaround type::
class ArrayOfEnum(ARRAY):
def bind_expression(self, bindvalue):
return sa.cast(bindvalue, self)
def result_processor(self, dialect, coltype):
super_rp = super(ArrayOfEnum, self).result_processor(
dialect, coltype)
def handle_raw_string(value):
inner = re.match(r"^{(.*)}$", value).group(1)
return inner.split(",") if inner else []
def process(value):
if value is None:
return None
return super_rp(handle_raw_string(value))
return process
E.g.::
Table(
'mydata', metadata,
Column('id', Integer, primary_key=True),
Column('data', ArrayOfEnum(ENUM('a', 'b, 'c', name='myenum')))
)
This type is not included as a built-in type as it would be incompatible
with a DBAPI that suddenly decides to support ARRAY of ENUM directly in
a new version.
.. _postgresql_array_of_json:
Using JSON/JSONB with ARRAY
^^^^^^^^^^^^^^^^^^^^^^^^^^^
Similar to using ENUM, for an ARRAY of JSON/JSONB we need to render the
appropriate CAST, however current psycopg2 drivers seem to handle the result
for ARRAY of JSON automatically, so the type is simpler::
class CastingArray(ARRAY):
def bind_expression(self, bindvalue):
return sa.cast(bindvalue, self)
E.g.::
Table(
'mydata', metadata,
Column('id', Integer, primary_key=True),
Column('data', CastingArray(JSONB))
)
"""
from collections import defaultdict
import re
import datetime as dt
from sqlalchemy.sql import elements
from ... import sql, schema, exc, util
from ...engine import default, reflection
from ...sql import compiler, expression
from ... import types as sqltypes
try:
from uuid import UUID as _python_UUID
except ImportError:
_python_UUID = None
from sqlalchemy.types import INTEGER, BIGINT, SMALLINT, VARCHAR, \
CHAR, TEXT, FLOAT, NUMERIC, \
DATE, BOOLEAN, REAL
AUTOCOMMIT_REGEXP = re.compile(
r'\s*(?:UPDATE|INSERT|CREATE|DELETE|DROP|ALTER|GRANT|REVOKE|'
'IMPORT FOREIGN SCHEMA|REFRESH MATERIALIZED VIEW)',
re.I | re.UNICODE)
RESERVED_WORDS = set(
["all", "analyse", "analyze", "and", "any", "array", "as", "asc",
"asymmetric", "both", "case", "cast", "check", "collate", "column",
"constraint", "create", "current_catalog", "current_date",
"current_role", "current_time", "current_timestamp", "current_user",
"default", "deferrable", "desc", "distinct", "do", "else", "end",
"except", "false", "fetch", "for", "foreign", "from", "grant", "group",
"having", "in", "initially", "intersect", "into", "leading", "limit",
"localtime", "localtimestamp", "new", "not", "null", "of", "off",
"offset", "old", "on", "only", "or", "order", "placing", "primary",
"references", "returning", "select", "session_user", "some", "symmetric",
"table", "then", "to", "trailing", "true", "union", "unique", "user",
"using", "variadic", "when", "where", "window", "with", "authorization",
"between", "binary", "cross", "current_schema", "freeze", "full",
"ilike", "inner", "is", "isnull", "join", "left", "like", "natural",
"notnull", "outer", "over", "overlaps", "right", "similar", "verbose"
])
_DECIMAL_TYPES = (1231, 1700)
_FLOAT_TYPES = (700, 701, 1021, 1022)
_INT_TYPES = (20, 21, 23, 26, 1005, 1007, 1016)
class BYTEA(sqltypes.LargeBinary):
__visit_name__ = 'BYTEA'
class DOUBLE_PRECISION(sqltypes.Float):
__visit_name__ = 'DOUBLE_PRECISION'
class INET(sqltypes.TypeEngine):
__visit_name__ = "INET"
PGInet = INET
class CIDR(sqltypes.TypeEngine):
__visit_name__ = "CIDR"
PGCidr = CIDR
class MACADDR(sqltypes.TypeEngine):
__visit_name__ = "MACADDR"
PGMacAddr = MACADDR
class OID(sqltypes.TypeEngine):
"""Provide the PostgreSQL OID type.
.. versionadded:: 0.9.5
"""
__visit_name__ = "OID"
class TIMESTAMP(sqltypes.TIMESTAMP):
def __init__(self, timezone=False, precision=None):
super(TIMESTAMP, self).__init__(timezone=timezone)
self.precision = precision
class TIME(sqltypes.TIME):
def __init__(self, timezone=False, precision=None):
super(TIME, self).__init__(timezone=timezone)
self.precision = precision
class INTERVAL(sqltypes.TypeEngine):
"""PostgreSQL INTERVAL type.
The INTERVAL type may not be supported on all DBAPIs.
It is known to work on psycopg2 and not pg8000 or zxjdbc.
"""
__visit_name__ = 'INTERVAL'
def __init__(self, precision=None):
self.precision = precision
@classmethod
def _adapt_from_generic_interval(cls, interval):
return INTERVAL(precision=interval.second_precision)
@property
def _type_affinity(self):
return sqltypes.Interval
@property
def python_type(self):
return dt.timedelta
PGInterval = INTERVAL
class BIT(sqltypes.TypeEngine):
__visit_name__ = 'BIT'
def __init__(self, length=None, varying=False):
if not varying:
# BIT without VARYING defaults to length 1
self.length = length or 1
else:
# but BIT VARYING can be unlimited-length, so no default
self.length = length
self.varying = varying
PGBit = BIT
class UUID(sqltypes.TypeEngine):
"""PostgreSQL UUID type.
Represents the UUID column type, interpreting
data either as natively returned by the DBAPI
or as Python uuid objects.
The UUID type may not be supported on all DBAPIs.
It is known to work on psycopg2 and not pg8000.
"""
__visit_name__ = 'UUID'
def __init__(self, as_uuid=False):
"""Construct a UUID type.
:param as_uuid=False: if True, values will be interpreted
as Python uuid objects, converting to/from string via the
DBAPI.
"""
if as_uuid and _python_UUID is None:
raise NotImplementedError(
"This version of Python does not support "
"the native UUID type."
)
self.as_uuid = as_uuid
def bind_processor(self, dialect):
if self.as_uuid:
def process(value):
if value is not None:
value = util.text_type(value)
return value
return process
else:
return None
def result_processor(self, dialect, coltype):
if self.as_uuid:
def process(value):
if value is not None:
value = _python_UUID(value)
return value
return process
else:
return None
PGUuid = UUID
class TSVECTOR(sqltypes.TypeEngine):
"""The :class:`.postgresql.TSVECTOR` type implements the PostgreSQL
text search type TSVECTOR.
It can be used to do full text queries on natural language
documents.
.. versionadded:: 0.9.0
.. seealso::
:ref:`postgresql_match`
"""
__visit_name__ = 'TSVECTOR'
class ENUM(sqltypes.Enum):
"""PostgreSQL ENUM type.
This is a subclass of :class:`.types.Enum` which includes
support for PG's ``CREATE TYPE`` and ``DROP TYPE``.
When the builtin type :class:`.types.Enum` is used and the
:paramref:`.Enum.native_enum` flag is left at its default of
True, the PostgreSQL backend will use a :class:`.postgresql.ENUM`
type as the implementation, so the special create/drop rules
will be used.
The create/drop behavior of ENUM is necessarily intricate, due to the
awkward relationship the ENUM type has in relationship to the
parent table, in that it may be "owned" by just a single table, or
may be shared among many tables.
When using :class:`.types.Enum` or :class:`.postgresql.ENUM`
in an "inline" fashion, the ``CREATE TYPE`` and ``DROP TYPE`` is emitted
corresponding to when the :meth:`.Table.create` and :meth:`.Table.drop`
methods are called::
table = Table('sometable', metadata,
Column('some_enum', ENUM('a', 'b', 'c', name='myenum'))
)
table.create(engine) # will emit CREATE ENUM and CREATE TABLE
table.drop(engine) # will emit DROP TABLE and DROP ENUM
To use a common enumerated type between multiple tables, the best
practice is to declare the :class:`.types.Enum` or
:class:`.postgresql.ENUM` independently, and associate it with the
:class:`.MetaData` object itself::
my_enum = ENUM('a', 'b', 'c', name='myenum', metadata=metadata)
t1 = Table('sometable_one', metadata,
Column('some_enum', myenum)
)
t2 = Table('sometable_two', metadata,
Column('some_enum', myenum)
)
When this pattern is used, care must still be taken at the level
of individual table creates. Emitting CREATE TABLE without also
specifying ``checkfirst=True`` will still cause issues::
t1.create(engine) # will fail: no such type 'myenum'
If we specify ``checkfirst=True``, the individual table-level create
operation will check for the ``ENUM`` and create if not exists::
# will check if enum exists, and emit CREATE TYPE if not
t1.create(engine, checkfirst=True)
When using a metadata-level ENUM type, the type will always be created
and dropped if either the metadata-wide create/drop is called::
metadata.create_all(engine) # will emit CREATE TYPE
metadata.drop_all(engine) # will emit DROP TYPE
The type can also be created and dropped directly::
my_enum.create(engine)
my_enum.drop(engine)
.. versionchanged:: 1.0.0 The PostgreSQL :class:`.postgresql.ENUM` type
now behaves more strictly with regards to CREATE/DROP. A metadata-level
ENUM type will only be created and dropped at the metadata level,
not the table level, with the exception of
``table.create(checkfirst=True)``.
The ``table.drop()`` call will now emit a DROP TYPE for a table-level
enumerated type.
"""
def __init__(self, *enums, **kw):
"""Construct an :class:`~.postgresql.ENUM`.
Arguments are the same as that of
:class:`.types.Enum`, but also including
the following parameters.
:param create_type: Defaults to True.
Indicates that ``CREATE TYPE`` should be
emitted, after optionally checking for the
presence of the type, when the parent
table is being created; and additionally
that ``DROP TYPE`` is called when the table
is dropped. When ``False``, no check
will be performed and no ``CREATE TYPE``
or ``DROP TYPE`` is emitted, unless
:meth:`~.postgresql.ENUM.create`
or :meth:`~.postgresql.ENUM.drop`
are called directly.
Setting to ``False`` is helpful
when invoking a creation scheme to a SQL file
without access to the actual database -
the :meth:`~.postgresql.ENUM.create` and
:meth:`~.postgresql.ENUM.drop` methods can
be used to emit SQL to a target bind.
.. versionadded:: 0.7.4
"""
self.create_type = kw.pop("create_type", True)
super(ENUM, self).__init__(*enums, **kw)
def create(self, bind=None, checkfirst=True):
"""Emit ``CREATE TYPE`` for this
:class:`~.postgresql.ENUM`.
If the underlying dialect does not support
PostgreSQL CREATE TYPE, no action is taken.
:param bind: a connectable :class:`.Engine`,
:class:`.Connection`, or similar object to emit
SQL.
:param checkfirst: if ``True``, a query against
the PG catalog will be first performed to see
if the type does not exist already before
creating.
"""
if not bind.dialect.supports_native_enum:
return
if not checkfirst or \
not bind.dialect.has_type(
bind, self.name, schema=self.schema):
bind.execute(CreateEnumType(self))
def drop(self, bind=None, checkfirst=True):
"""Emit ``DROP TYPE`` for this
:class:`~.postgresql.ENUM`.
If the underlying dialect does not support
PostgreSQL DROP TYPE, no action is taken.
:param bind: a connectable :class:`.Engine`,
:class:`.Connection`, or similar object to emit
SQL.
:param checkfirst: if ``True``, a query against
the PG catalog will be first performed to see
if the type actually exists before dropping.
"""
if not bind.dialect.supports_native_enum:
return
if not checkfirst or \
bind.dialect.has_type(bind, self.name, schema=self.schema):
bind.execute(DropEnumType(self))
def _check_for_name_in_memos(self, checkfirst, kw):
"""Look in the 'ddl runner' for 'memos', then
note our name in that collection.
This to ensure a particular named enum is operated
upon only once within any kind of create/drop
sequence without relying upon "checkfirst".
"""
if not self.create_type:
return True
if '_ddl_runner' in kw:
ddl_runner = kw['_ddl_runner']
if '_pg_enums' in ddl_runner.memo:
pg_enums = ddl_runner.memo['_pg_enums']
else:
pg_enums = ddl_runner.memo['_pg_enums'] = set()
present = self.name in pg_enums
pg_enums.add(self.name)
return present
else:
return False
def _on_table_create(self, target, bind, checkfirst=False, **kw):
if checkfirst or (
not self.metadata and
not kw.get('_is_metadata_operation', False)) and \
not self._check_for_name_in_memos(checkfirst, kw):
self.create(bind=bind, checkfirst=checkfirst)
def _on_table_drop(self, target, bind, checkfirst=False, **kw):
if not self.metadata and \
not kw.get('_is_metadata_operation', False) and \
not self._check_for_name_in_memos(checkfirst, kw):
self.drop(bind=bind, checkfirst=checkfirst)
def _on_metadata_create(self, target, bind, checkfirst=False, **kw):
if not self._check_for_name_in_memos(checkfirst, kw):
self.create(bind=bind, checkfirst=checkfirst)
def _on_metadata_drop(self, target, bind, checkfirst=False, **kw):
if not self._check_for_name_in_memos(checkfirst, kw):
self.drop(bind=bind, checkfirst=checkfirst)
colspecs = {
sqltypes.Interval: INTERVAL,
sqltypes.Enum: ENUM,
}
ischema_names = {
'integer': INTEGER,
'bigint': BIGINT,
'smallint': SMALLINT,
'character varying': VARCHAR,
'character': CHAR,
'"char"': sqltypes.String,
'name': sqltypes.String,
'text': TEXT,
'numeric': NUMERIC,
'float': FLOAT,
'real': REAL,
'inet': INET,
'cidr': CIDR,
'uuid': UUID,
'bit': BIT,
'bit varying': BIT,
'macaddr': MACADDR,
'oid': OID,
'double precision': DOUBLE_PRECISION,
'timestamp': TIMESTAMP,
'timestamp with time zone': TIMESTAMP,
'timestamp without time zone': TIMESTAMP,
'time with time zone': TIME,
'time without time zone': TIME,
'date': DATE,
'time': TIME,
'bytea': BYTEA,
'boolean': BOOLEAN,
'interval': INTERVAL,
'interval year to month': INTERVAL,
'interval day to second': INTERVAL,
'tsvector': TSVECTOR
}
class PGCompiler(compiler.SQLCompiler):
def visit_array(self, element, **kw):
return "ARRAY[%s]" % self.visit_clauselist(element, **kw)
def visit_slice(self, element, **kw):
return "%s:%s" % (
self.process(element.start, **kw),
self.process(element.stop, **kw),
)
def visit_json_getitem_op_binary(self, binary, operator, **kw):
kw['eager_grouping'] = True
return self._generate_generic_binary(
binary, " -> ", **kw
)
def visit_json_path_getitem_op_binary(self, binary, operator, **kw):
kw['eager_grouping'] = True
return self._generate_generic_binary(
binary, " #> ", **kw
)
def visit_getitem_binary(self, binary, operator, **kw):
return "%s[%s]" % (
self.process(binary.left, **kw),
self.process(binary.right, **kw)
)
def visit_aggregate_order_by(self, element, **kw):
return "%s ORDER BY %s" % (
self.process(element.target, **kw),
self.process(element.order_by, **kw)
)
def visit_match_op_binary(self, binary, operator, **kw):
if "postgresql_regconfig" in binary.modifiers:
regconfig = self.render_literal_value(
binary.modifiers['postgresql_regconfig'],
sqltypes.STRINGTYPE)
if regconfig:
return "%s @@ to_tsquery(%s, %s)" % (
self.process(binary.left, **kw),
regconfig,
self.process(binary.right, **kw)
)
return "%s @@ to_tsquery(%s)" % (
self.process(binary.left, **kw),
self.process(binary.right, **kw)
)
def visit_ilike_op_binary(self, binary, operator, **kw):
escape = binary.modifiers.get("escape", None)
return '%s ILIKE %s' % \
(self.process(binary.left, **kw),
self.process(binary.right, **kw)) \
+ (
' ESCAPE ' +
self.render_literal_value(escape, sqltypes.STRINGTYPE)
if escape else ''
)
def visit_notilike_op_binary(self, binary, operator, **kw):
escape = binary.modifiers.get("escape", None)
return '%s NOT ILIKE %s' % \
(self.process(binary.left, **kw),
self.process(binary.right, **kw)) \
+ (
' ESCAPE ' +
self.render_literal_value(escape, sqltypes.STRINGTYPE)
if escape else ''
)
def render_literal_value(self, value, type_):
value = super(PGCompiler, self).render_literal_value(value, type_)
if self.dialect._backslash_escapes:
value = value.replace('\\', '\\\\')
return value
def visit_sequence(self, seq):
return "nextval('%s')" % self.preparer.format_sequence(seq)
def limit_clause(self, select, **kw):
text = ""
if select._limit_clause is not None:
text += " \n LIMIT " + self.process(select._limit_clause, **kw)
if select._offset_clause is not None:
if select._limit_clause is None:
text += " \n LIMIT ALL"
text += " OFFSET " + self.process(select._offset_clause, **kw)
return text
def format_from_hint_text(self, sqltext, table, hint, iscrud):
if hint.upper() != 'ONLY':
raise exc.CompileError("Unrecognized hint: %r" % hint)
return "ONLY " + sqltext
def get_select_precolumns(self, select, **kw):
if select._distinct is not False:
if select._distinct is True:
return "DISTINCT "
elif isinstance(select._distinct, (list, tuple)):
return "DISTINCT ON (" + ', '.join(
[self.process(col) for col in select._distinct]
) + ") "
else:
return "DISTINCT ON (" + \
self.process(select._distinct, **kw) + ") "
else:
return ""
def for_update_clause(self, select, **kw):
if select._for_update_arg.read:
if select._for_update_arg.key_share:
tmp = " FOR KEY SHARE"
else:
tmp = " FOR SHARE"
elif select._for_update_arg.key_share:
tmp = " FOR NO KEY UPDATE"
else:
tmp = " FOR UPDATE"
if select._for_update_arg.of:
tables = util.OrderedSet(
c.table if isinstance(c, expression.ColumnClause)
else c for c in select._for_update_arg.of)
tmp += " OF " + ", ".join(
self.process(table, ashint=True, use_schema=False, **kw)
for table in tables
)
if select._for_update_arg.nowait:
tmp += " NOWAIT"
if select._for_update_arg.skip_locked:
tmp += " SKIP LOCKED"
return tmp
def returning_clause(self, stmt, returning_cols):
columns = [
self._label_select_column(None, c, True, False, {})
for c in expression._select_iterables(returning_cols)
]
return 'RETURNING ' + ', '.join(columns)
def visit_substring_func(self, func, **kw):
s = self.process(func.clauses.clauses[0], **kw)
start = self.process(func.clauses.clauses[1], **kw)
if len(func.clauses.clauses) > 2:
length = self.process(func.clauses.clauses[2], **kw)
return "SUBSTRING(%s FROM %s FOR %s)" % (s, start, length)
else:
return "SUBSTRING(%s FROM %s)" % (s, start)
def _on_conflict_target(self, clause, **kw):
if clause.constraint_target is not None:
target_text = 'ON CONSTRAINT %s' % clause.constraint_target
elif clause.inferred_target_elements is not None:
target_text = '(%s)' % ', '.join(
(self.preparer.quote(c)
if isinstance(c, util.string_types)
else
self.process(c, include_table=False, use_schema=False))
for c in clause.inferred_target_elements
)
if clause.inferred_target_whereclause is not None:
target_text += ' WHERE %s' % \
self.process(
clause.inferred_target_whereclause,
include_table=False,
use_schema=False
)
else:
target_text = ''
return target_text
def visit_on_conflict_do_nothing(self, on_conflict, **kw):
target_text = self._on_conflict_target(on_conflict, **kw)
if target_text:
return "ON CONFLICT %s DO NOTHING" % target_text
else:
return "ON CONFLICT DO NOTHING"
def visit_on_conflict_do_update(self, on_conflict, **kw):
clause = on_conflict
target_text = self._on_conflict_target(on_conflict, **kw)
action_set_ops = []
set_parameters = dict(clause.update_values_to_set)
# create a list of column assignment clauses as tuples
cols = self.statement.table.c
for c in cols:
col_key = c.key
if col_key in set_parameters:
value = set_parameters.pop(col_key)
if elements._is_literal(value):
value = elements.BindParameter(
None, value, type_=c.type
)
else:
if isinstance(value, elements.BindParameter) and \
value.type._isnull:
value = value._clone()
value.type = c.type
value_text = self.process(value.self_group(), use_schema=False)
key_text = (
self.preparer.quote(col_key)
)
action_set_ops.append('%s = %s' % (key_text, value_text))
# check for names that don't match columns
if set_parameters:
util.warn(
"Additional column names not matching "
"any column keys in table '%s': %s" % (
self.statement.table.name,
(", ".join("'%s'" % c for c in set_parameters))
)
)
for k, v in set_parameters.items():
key_text = (
self.preparer.quote(k)
if isinstance(k, util.string_types)
else self.process(k, use_schema=False)
)
value_text = self.process(
elements._literal_as_binds(v),
use_schema=False
)
action_set_ops.append('%s = %s' % (key_text, value_text))
action_text = ', '.join(action_set_ops)
if clause.update_whereclause is not None:
action_text += ' WHERE %s' % \
self.process(
clause.update_whereclause,
include_table=True,
use_schema=False
)
return 'ON CONFLICT %s DO UPDATE SET %s' % (target_text, action_text)
class PGDDLCompiler(compiler.DDLCompiler):
def get_column_specification(self, column, **kwargs):
colspec = self.preparer.format_column(column)
impl_type = column.type.dialect_impl(self.dialect)
if isinstance(impl_type, sqltypes.TypeDecorator):
impl_type = impl_type.impl
if column.primary_key and \
column is column.table._autoincrement_column and \
(
self.dialect.supports_smallserial or
not isinstance(impl_type, sqltypes.SmallInteger)
) and (
column.default is None or
(
isinstance(column.default, schema.Sequence) and
column.default.optional
)):
if isinstance(impl_type, sqltypes.BigInteger):
colspec += " BIGSERIAL"
elif isinstance(impl_type, sqltypes.SmallInteger):
colspec += " SMALLSERIAL"
else:
colspec += " SERIAL"
else:
colspec += " " + self.dialect.type_compiler.process(
column.type, type_expression=column)
default = self.get_column_default_string(column)
if default is not None:
colspec += " DEFAULT " + default
if not column.nullable:
colspec += " NOT NULL"
return colspec
def visit_create_enum_type(self, create):
type_ = create.element
return "CREATE TYPE %s AS ENUM (%s)" % (
self.preparer.format_type(type_),
", ".join(
self.sql_compiler.process(sql.literal(e), literal_binds=True)
for e in type_.enums)
)
def visit_drop_enum_type(self, drop):
type_ = drop.element
return "DROP TYPE %s" % (
self.preparer.format_type(type_)
)
def visit_create_index(self, create):
preparer = self.preparer
index = create.element
self._verify_index_table(index)
text = "CREATE "
if index.unique:
text += "UNIQUE "
text += "INDEX "
if self.dialect._supports_create_index_concurrently:
concurrently = index.dialect_options['postgresql']['concurrently']
if concurrently:
text += "CONCURRENTLY "
text += "%s ON %s " % (
self._prepared_index_name(index,
include_schema=False),
preparer.format_table(index.table)
)
using = index.dialect_options['postgresql']['using']
if using:
text += "USING %s " % preparer.quote(using)
ops = index.dialect_options["postgresql"]["ops"]
text += "(%s)" \
% (
', '.join([
self.sql_compiler.process(
expr.self_group()
if not isinstance(expr, expression.ColumnClause)
else expr,
include_table=False, literal_binds=True) +
(
(' ' + ops[expr.key])
if hasattr(expr, 'key')
and expr.key in ops else ''
)
for expr in index.expressions
])
)
withclause = index.dialect_options['postgresql']['with']
if withclause:
text += " WITH (%s)" % (', '.join(
['%s = %s' % storage_parameter
for storage_parameter in withclause.items()]))
tablespace_name = index.dialect_options['postgresql']['tablespace']
if tablespace_name:
text += " TABLESPACE %s" % preparer.quote(tablespace_name)
whereclause = index.dialect_options["postgresql"]["where"]
if whereclause is not None:
where_compiled = self.sql_compiler.process(
whereclause, include_table=False,
literal_binds=True)
text += " WHERE " + where_compiled
return text
def visit_drop_index(self, drop):
index = drop.element
text = "\nDROP INDEX "
if self.dialect._supports_drop_index_concurrently:
concurrently = index.dialect_options['postgresql']['concurrently']
if concurrently:
text += "CONCURRENTLY "
text += self._prepared_index_name(index, include_schema=True)
return text
def visit_exclude_constraint(self, constraint, **kw):
text = ""
if constraint.name is not None:
text += "CONSTRAINT %s " % \
self.preparer.format_constraint(constraint)
elements = []
for expr, name, op in constraint._render_exprs:
kw['include_table'] = False
elements.append(
"%s WITH %s" % (self.sql_compiler.process(expr, **kw), op)
)
text += "EXCLUDE USING %s (%s)" % (constraint.using,
', '.join(elements))
if constraint.where is not None:
text += ' WHERE (%s)' % self.sql_compiler.process(
constraint.where,
literal_binds=True)
text += self.define_constraint_deferrability(constraint)
return text
def post_create_table(self, table):
table_opts = []
pg_opts = table.dialect_options['postgresql']
inherits = pg_opts.get('inherits')
if inherits is not None:
if not isinstance(inherits, (list, tuple)):
inherits = (inherits, )
table_opts.append(
'\n INHERITS ( ' +
', '.join(self.preparer.quote(name) for name in inherits) +
' )')
if pg_opts['with_oids'] is True:
table_opts.append('\n WITH OIDS')
elif pg_opts['with_oids'] is False:
table_opts.append('\n WITHOUT OIDS')
if pg_opts['on_commit']:
on_commit_options = pg_opts['on_commit'].replace("_", " ").upper()
table_opts.append('\n ON COMMIT %s' % on_commit_options)
if pg_opts['tablespace']:
tablespace_name = pg_opts['tablespace']
table_opts.append(
'\n TABLESPACE %s' % self.preparer.quote(tablespace_name)
)
return ''.join(table_opts)
class PGTypeCompiler(compiler.GenericTypeCompiler):
def visit_TSVECTOR(self, type, **kw):
return "TSVECTOR"
def visit_INET(self, type_, **kw):
return "INET"
def visit_CIDR(self, type_, **kw):
return "CIDR"
def visit_MACADDR(self, type_, **kw):
return "MACADDR"
def visit_OID(self, type_, **kw):
return "OID"
def visit_FLOAT(self, type_, **kw):
if not type_.precision:
return "FLOAT"
else:
return "FLOAT(%(precision)s)" % {'precision': type_.precision}
def visit_DOUBLE_PRECISION(self, type_, **kw):
return "DOUBLE PRECISION"
def visit_BIGINT(self, type_, **kw):
return "BIGINT"
def visit_HSTORE(self, type_, **kw):
return "HSTORE"
def visit_JSON(self, type_, **kw):
return "JSON"
def visit_JSONB(self, type_, **kw):
return "JSONB"
def visit_INT4RANGE(self, type_, **kw):
return "INT4RANGE"
def visit_INT8RANGE(self, type_, **kw):
return "INT8RANGE"
def visit_NUMRANGE(self, type_, **kw):
return "NUMRANGE"
def visit_DATERANGE(self, type_, **kw):
return "DATERANGE"
def visit_TSRANGE(self, type_, **kw):
return "TSRANGE"
def visit_TSTZRANGE(self, type_, **kw):
return "TSTZRANGE"
def visit_datetime(self, type_, **kw):
return self.visit_TIMESTAMP(type_, **kw)
def visit_enum(self, type_, **kw):
if not type_.native_enum or not self.dialect.supports_native_enum:
return super(PGTypeCompiler, self).visit_enum(type_, **kw)
else:
return self.visit_ENUM(type_, **kw)
def visit_ENUM(self, type_, **kw):
return self.dialect.identifier_preparer.format_type(type_)
def visit_TIMESTAMP(self, type_, **kw):
return "TIMESTAMP%s %s" % (
"(%d)" % type_.precision
if getattr(type_, 'precision', None) is not None else "",
(type_.timezone and "WITH" or "WITHOUT") + " TIME ZONE"
)
def visit_TIME(self, type_, **kw):
return "TIME%s %s" % (
"(%d)" % type_.precision
if getattr(type_, 'precision', None) is not None else "",
(type_.timezone and "WITH" or "WITHOUT") + " TIME ZONE"
)
def visit_INTERVAL(self, type_, **kw):
if type_.precision is not None:
return "INTERVAL(%d)" % type_.precision
else:
return "INTERVAL"
def visit_BIT(self, type_, **kw):
if type_.varying:
compiled = "BIT VARYING"
if type_.length is not None:
compiled += "(%d)" % type_.length
else:
compiled = "BIT(%d)" % type_.length
return compiled
def visit_UUID(self, type_, **kw):
return "UUID"
def visit_large_binary(self, type_, **kw):
return self.visit_BYTEA(type_, **kw)
def visit_BYTEA(self, type_, **kw):
return "BYTEA"
def visit_ARRAY(self, type_, **kw):
# TODO: pass **kw?
inner = self.process(type_.item_type)
return re.sub(
r'((?: COLLATE.*)?)$',
(r'[]\1' *
(type_.dimensions if type_.dimensions is not None else 1)),
inner
)
class PGIdentifierPreparer(compiler.IdentifierPreparer):
reserved_words = RESERVED_WORDS
def _unquote_identifier(self, value):
if value[0] == self.initial_quote:
value = value[1:-1].\
replace(self.escape_to_quote, self.escape_quote)
return value
def format_type(self, type_, use_schema=True):
if not type_.name:
raise exc.CompileError("PostgreSQL ENUM type requires a name.")
name = self.quote(type_.name)
effective_schema = self.schema_for_object(type_)
if not self.omit_schema and use_schema and \
effective_schema is not None:
name = self.quote_schema(effective_schema) + "." + name
return name
class PGInspector(reflection.Inspector):
def __init__(self, conn):
reflection.Inspector.__init__(self, conn)
def get_table_oid(self, table_name, schema=None):
"""Return the OID for the given table name."""
return self.dialect.get_table_oid(self.bind, table_name, schema,
info_cache=self.info_cache)
def get_enums(self, schema=None):
"""Return a list of ENUM objects.
Each member is a dictionary containing these fields:
* name - name of the enum
* schema - the schema name for the enum.
* visible - boolean, whether or not this enum is visible
in the default search path.
* labels - a list of string labels that apply to the enum.
:param schema: schema name. If None, the default schema
(typically 'public') is used. May also be set to '*' to
indicate load enums for all schemas.
.. versionadded:: 1.0.0
"""
schema = schema or self.default_schema_name
return self.dialect._load_enums(self.bind, schema)
def get_foreign_table_names(self, schema=None):
"""Return a list of FOREIGN TABLE names.
Behavior is similar to that of :meth:`.Inspector.get_table_names`,
except that the list is limited to those tables tha report a
``relkind`` value of ``f``.
.. versionadded:: 1.0.0
"""
schema = schema or self.default_schema_name
return self.dialect._get_foreign_table_names(self.bind, schema)
def get_view_names(self, schema=None, include=('plain', 'materialized')):
"""Return all view names in `schema`.
:param schema: Optional, retrieve names from a non-default schema.
For special quoting, use :class:`.quoted_name`.
:param include: specify which types of views to return. Passed
as a string value (for a single type) or a tuple (for any number
of types). Defaults to ``('plain', 'materialized')``.
.. versionadded:: 1.1
"""
return self.dialect.get_view_names(self.bind, schema,
info_cache=self.info_cache,
include=include)
class CreateEnumType(schema._CreateDropBase):
__visit_name__ = "create_enum_type"
class DropEnumType(schema._CreateDropBase):
__visit_name__ = "drop_enum_type"
class PGExecutionContext(default.DefaultExecutionContext):
def fire_sequence(self, seq, type_):
return self._execute_scalar((
"select nextval('%s')" %
self.dialect.identifier_preparer.format_sequence(seq)), type_)
def get_insert_default(self, column):
if column.primary_key and \
column is column.table._autoincrement_column:
if column.server_default and column.server_default.has_argument:
# pre-execute passive defaults on primary key columns
return self._execute_scalar("select %s" %
column.server_default.arg,
column.type)
elif (column.default is None or
(column.default.is_sequence and
column.default.optional)):
# execute the sequence associated with a SERIAL primary
# key column. for non-primary-key SERIAL, the ID just
# generates server side.
try:
seq_name = column._postgresql_seq_name
except AttributeError:
tab = column.table.name
col = column.name
tab = tab[0:29 + max(0, (29 - len(col)))]
col = col[0:29 + max(0, (29 - len(tab)))]
name = "%s_%s_seq" % (tab, col)
column._postgresql_seq_name = seq_name = name
if column.table is not None:
effective_schema = self.connection.schema_for_object(
column.table)
else:
effective_schema = None
if effective_schema is not None:
exc = "select nextval('\"%s\".\"%s\"')" % \
(effective_schema, seq_name)
else:
exc = "select nextval('\"%s\"')" % \
(seq_name, )
return self._execute_scalar(exc, column.type)
return super(PGExecutionContext, self).get_insert_default(column)
def should_autocommit_text(self, statement):
return AUTOCOMMIT_REGEXP.match(statement)
class PGDialect(default.DefaultDialect):
name = 'postgresql'
supports_alter = True
max_identifier_length = 63
supports_sane_rowcount = True
supports_native_enum = True
supports_native_boolean = True
supports_smallserial = True
supports_sequences = True
sequences_optional = True
preexecute_autoincrement_sequences = True
postfetch_lastrowid = False
supports_default_values = True
supports_empty_insert = False
supports_multivalues_insert = True
default_paramstyle = 'pyformat'
ischema_names = ischema_names
colspecs = colspecs
statement_compiler = PGCompiler
ddl_compiler = PGDDLCompiler
type_compiler = PGTypeCompiler
preparer = PGIdentifierPreparer
execution_ctx_cls = PGExecutionContext
inspector = PGInspector
isolation_level = None
construct_arguments = [
(schema.Index, {
"using": False,
"where": None,
"ops": {},
"concurrently": False,
"with": {},
"tablespace": None
}),
(schema.Table, {
"ignore_search_path": False,
"tablespace": None,
"with_oids": None,
"on_commit": None,
"inherits": None
}),
]
reflection_options = ('postgresql_ignore_search_path', )
_backslash_escapes = True
_supports_create_index_concurrently = True
_supports_drop_index_concurrently = True
def __init__(self, isolation_level=None, json_serializer=None,
json_deserializer=None, **kwargs):
default.DefaultDialect.__init__(self, **kwargs)
self.isolation_level = isolation_level
self._json_deserializer = json_deserializer
self._json_serializer = json_serializer
def initialize(self, connection):
super(PGDialect, self).initialize(connection)
self.implicit_returning = self.server_version_info > (8, 2) and \
self.__dict__.get('implicit_returning', True)
self.supports_native_enum = self.server_version_info >= (8, 3)
if not self.supports_native_enum:
self.colspecs = self.colspecs.copy()
# pop base Enum type
self.colspecs.pop(sqltypes.Enum, None)
# psycopg2, others may have placed ENUM here as well
self.colspecs.pop(ENUM, None)
# http://www.postgresql.org/docs/9.3/static/release-9-2.html#AEN116689
self.supports_smallserial = self.server_version_info >= (9, 2)
self._backslash_escapes = self.server_version_info < (8, 2) or \
connection.scalar(
"show standard_conforming_strings"
) == 'off'
self._supports_create_index_concurrently = \
self.server_version_info >= (8, 2)
self._supports_drop_index_concurrently = \
self.server_version_info >= (9, 2)
def on_connect(self):
if self.isolation_level is not None:
def connect(conn):
self.set_isolation_level(conn, self.isolation_level)
return connect
else:
return None
_isolation_lookup = set(['SERIALIZABLE', 'READ UNCOMMITTED',
'READ COMMITTED', 'REPEATABLE READ'])
def set_isolation_level(self, connection, level):
level = level.replace('_', ' ')
if level not in self._isolation_lookup:
raise exc.ArgumentError(
"Invalid value '%s' for isolation_level. "
"Valid isolation levels for %s are %s" %
(level, self.name, ", ".join(self._isolation_lookup))
)
cursor = connection.cursor()
cursor.execute(
"SET SESSION CHARACTERISTICS AS TRANSACTION "
"ISOLATION LEVEL %s" % level)
cursor.execute("COMMIT")
cursor.close()
def get_isolation_level(self, connection):
cursor = connection.cursor()
cursor.execute('show transaction isolation level')
val = cursor.fetchone()[0]
cursor.close()
return val.upper()
def do_begin_twophase(self, connection, xid):
self.do_begin(connection.connection)
def do_prepare_twophase(self, connection, xid):
connection.execute("PREPARE TRANSACTION '%s'" % xid)
def do_rollback_twophase(self, connection, xid,
is_prepared=True, recover=False):
if is_prepared:
if recover:
# FIXME: ugly hack to get out of transaction
# context when committing recoverable transactions
# Must find out a way how to make the dbapi not
# open a transaction.
connection.execute("ROLLBACK")
connection.execute("ROLLBACK PREPARED '%s'" % xid)
connection.execute("BEGIN")
self.do_rollback(connection.connection)
else:
self.do_rollback(connection.connection)
def do_commit_twophase(self, connection, xid,
is_prepared=True, recover=False):
if is_prepared:
if recover:
connection.execute("ROLLBACK")
connection.execute("COMMIT PREPARED '%s'" % xid)
connection.execute("BEGIN")
self.do_rollback(connection.connection)
else:
self.do_commit(connection.connection)
def do_recover_twophase(self, connection):
resultset = connection.execute(
sql.text("SELECT gid FROM pg_prepared_xacts"))
return [row[0] for row in resultset]
def _get_default_schema_name(self, connection):
return connection.scalar("select current_schema()")
def has_schema(self, connection, schema):
query = ("select nspname from pg_namespace "
"where lower(nspname)=:schema")
cursor = connection.execute(
sql.text(
query,
bindparams=[
sql.bindparam(
'schema', util.text_type(schema.lower()),
type_=sqltypes.Unicode)]
)
)
return bool(cursor.first())
def has_table(self, connection, table_name, schema=None):
# seems like case gets folded in pg_class...
if schema is None:
cursor = connection.execute(
sql.text(
"select relname from pg_class c join pg_namespace n on "
"n.oid=c.relnamespace where "
"pg_catalog.pg_table_is_visible(c.oid) "
"and relname=:name",
bindparams=[
sql.bindparam('name', util.text_type(table_name),
type_=sqltypes.Unicode)]
)
)
else:
cursor = connection.execute(
sql.text(
"select relname from pg_class c join pg_namespace n on "
"n.oid=c.relnamespace where n.nspname=:schema and "
"relname=:name",
bindparams=[
sql.bindparam('name',
util.text_type(table_name),
type_=sqltypes.Unicode),
sql.bindparam('schema',
util.text_type(schema),
type_=sqltypes.Unicode)]
)
)
return bool(cursor.first())
def has_sequence(self, connection, sequence_name, schema=None):
if schema is None:
cursor = connection.execute(
sql.text(
"SELECT relname FROM pg_class c join pg_namespace n on "
"n.oid=c.relnamespace where relkind='S' and "
"n.nspname=current_schema() "
"and relname=:name",
bindparams=[
sql.bindparam('name', util.text_type(sequence_name),
type_=sqltypes.Unicode)
]
)
)
else:
cursor = connection.execute(
sql.text(
"SELECT relname FROM pg_class c join pg_namespace n on "
"n.oid=c.relnamespace where relkind='S' and "
"n.nspname=:schema and relname=:name",
bindparams=[
sql.bindparam('name', util.text_type(sequence_name),
type_=sqltypes.Unicode),
sql.bindparam('schema',
util.text_type(schema),
type_=sqltypes.Unicode)
]
)
)
return bool(cursor.first())
def has_type(self, connection, type_name, schema=None):
if schema is not None:
query = """
SELECT EXISTS (
SELECT * FROM pg_catalog.pg_type t, pg_catalog.pg_namespace n
WHERE t.typnamespace = n.oid
AND t.typname = :typname
AND n.nspname = :nspname
)
"""
query = sql.text(query)
else:
query = """
SELECT EXISTS (
SELECT * FROM pg_catalog.pg_type t
WHERE t.typname = :typname
AND pg_type_is_visible(t.oid)
)
"""
query = sql.text(query)
query = query.bindparams(
sql.bindparam('typname',
util.text_type(type_name), type_=sqltypes.Unicode),
)
if schema is not None:
query = query.bindparams(
sql.bindparam('nspname',
util.text_type(schema), type_=sqltypes.Unicode),
)
cursor = connection.execute(query)
return bool(cursor.scalar())
def _get_server_version_info(self, connection):
v = connection.execute("select version()").scalar()
m = re.match(
r'.*(?:PostgreSQL|EnterpriseDB) '
r'(\d+)\.?(\d+)?(?:\.(\d+))?(?:\.\d+)?(?:devel|beta)?',
v)
if not m:
raise AssertionError(
"Could not determine version from string '%s'" % v)
return tuple([int(x) for x in m.group(1, 2, 3) if x is not None])
@reflection.cache
def get_table_oid(self, connection, table_name, schema=None, **kw):
"""Fetch the oid for schema.table_name.
Several reflection methods require the table oid. The idea for using
this method is that it can be fetched one time and cached for
subsequent calls.
"""
table_oid = None
if schema is not None:
schema_where_clause = "n.nspname = :schema"
else:
schema_where_clause = "pg_catalog.pg_table_is_visible(c.oid)"
query = """
SELECT c.oid
FROM pg_catalog.pg_class c
LEFT JOIN pg_catalog.pg_namespace n ON n.oid = c.relnamespace
WHERE (%s)
AND c.relname = :table_name AND c.relkind in ('r', 'v', 'm', 'f')
""" % schema_where_clause
# Since we're binding to unicode, table_name and schema_name must be
# unicode.
table_name = util.text_type(table_name)
if schema is not None:
schema = util.text_type(schema)
s = sql.text(query).bindparams(table_name=sqltypes.Unicode)
s = s.columns(oid=sqltypes.Integer)
if schema:
s = s.bindparams(sql.bindparam('schema', type_=sqltypes.Unicode))
c = connection.execute(s, table_name=table_name, schema=schema)
table_oid = c.scalar()
if table_oid is None:
raise exc.NoSuchTableError(table_name)
return table_oid
@reflection.cache
def get_schema_names(self, connection, **kw):
result = connection.execute(
sql.text("SELECT nspname FROM pg_namespace "
"WHERE nspname NOT LIKE 'pg_%' "
"ORDER BY nspname"
).columns(nspname=sqltypes.Unicode))
return [name for name, in result]
@reflection.cache
def get_table_names(self, connection, schema=None, **kw):
result = connection.execute(
sql.text("SELECT c.relname FROM pg_class c "
"JOIN pg_namespace n ON n.oid = c.relnamespace "
"WHERE n.nspname = :schema AND c.relkind = 'r'"
).columns(relname=sqltypes.Unicode),
schema=schema if schema is not None else self.default_schema_name)
return [name for name, in result]
@reflection.cache
def _get_foreign_table_names(self, connection, schema=None, **kw):
result = connection.execute(
sql.text("SELECT c.relname FROM pg_class c "
"JOIN pg_namespace n ON n.oid = c.relnamespace "
"WHERE n.nspname = :schema AND c.relkind = 'f'"
).columns(relname=sqltypes.Unicode),
schema=schema if schema is not None else self.default_schema_name)
return [name for name, in result]
@reflection.cache
def get_view_names(
self, connection, schema=None,
include=('plain', 'materialized'), **kw):
include_kind = {'plain': 'v', 'materialized': 'm'}
try:
kinds = [include_kind[i] for i in util.to_list(include)]
except KeyError:
raise ValueError(
"include %r unknown, needs to be a sequence containing "
"one or both of 'plain' and 'materialized'" % (include,))
if not kinds:
raise ValueError(
"empty include, needs to be a sequence containing "
"one or both of 'plain' and 'materialized'")
result = connection.execute(
sql.text("SELECT c.relname FROM pg_class c "
"JOIN pg_namespace n ON n.oid = c.relnamespace "
"WHERE n.nspname = :schema AND c.relkind IN (%s)" %
(", ".join("'%s'" % elem for elem in kinds))
).columns(relname=sqltypes.Unicode),
schema=schema if schema is not None else self.default_schema_name)
return [name for name, in result]
@reflection.cache
def get_view_definition(self, connection, view_name, schema=None, **kw):
view_def = connection.scalar(
sql.text("SELECT pg_get_viewdef(c.oid) view_def FROM pg_class c "
"JOIN pg_namespace n ON n.oid = c.relnamespace "
"WHERE n.nspname = :schema AND c.relname = :view_name "
"AND c.relkind IN ('v', 'm')"
).columns(view_def=sqltypes.Unicode),
schema=schema if schema is not None else self.default_schema_name,
view_name=view_name)
return view_def
@reflection.cache
def get_columns(self, connection, table_name, schema=None, **kw):
table_oid = self.get_table_oid(connection, table_name, schema,
info_cache=kw.get('info_cache'))
SQL_COLS = """
SELECT a.attname,
pg_catalog.format_type(a.atttypid, a.atttypmod),
(SELECT pg_catalog.pg_get_expr(d.adbin, d.adrelid)
FROM pg_catalog.pg_attrdef d
WHERE d.adrelid = a.attrelid AND d.adnum = a.attnum
AND a.atthasdef)
AS DEFAULT,
a.attnotnull, a.attnum, a.attrelid as table_oid
FROM pg_catalog.pg_attribute a
WHERE a.attrelid = :table_oid
AND a.attnum > 0 AND NOT a.attisdropped
ORDER BY a.attnum
"""
s = sql.text(SQL_COLS,
bindparams=[
sql.bindparam('table_oid', type_=sqltypes.Integer)],
typemap={
'attname': sqltypes.Unicode,
'default': sqltypes.Unicode}
)
c = connection.execute(s, table_oid=table_oid)
rows = c.fetchall()
domains = self._load_domains(connection)
enums = dict(
(
"%s.%s" % (rec['schema'], rec['name'])
if not rec['visible'] else rec['name'], rec) for rec in
self._load_enums(connection, schema='*')
)
# format columns
columns = []
for name, format_type, default, notnull, attnum, table_oid in rows:
column_info = self._get_column_info(
name, format_type, default, notnull, domains, enums, schema)
columns.append(column_info)
return columns
def _get_column_info(self, name, format_type, default,
notnull, domains, enums, schema):
# strip (*) from character varying(5), timestamp(5)
# with time zone, geometry(POLYGON), etc.
attype = re.sub(r'\(.*\)', '', format_type)
# strip '[]' from integer[], etc.
attype = attype.replace('[]', '')
nullable = not notnull
is_array = format_type.endswith('[]')
charlen = re.search(r'\(([\d,]+)\)', format_type)
if charlen:
charlen = charlen.group(1)
args = re.search(r'\((.*)\)', format_type)
if args and args.group(1):
args = tuple(re.split(r'\s*,\s*', args.group(1)))
else:
args = ()
kwargs = {}
if attype == 'numeric':
if charlen:
prec, scale = charlen.split(',')
args = (int(prec), int(scale))
else:
args = ()
elif attype == 'double precision':
args = (53, )
elif attype == 'integer':
args = ()
elif attype in ('timestamp with time zone',
'time with time zone'):
kwargs['timezone'] = True
if charlen:
kwargs['precision'] = int(charlen)
args = ()
elif attype in ('timestamp without time zone',
'time without time zone', 'time'):
kwargs['timezone'] = False
if charlen:
kwargs['precision'] = int(charlen)
args = ()
elif attype == 'bit varying':
kwargs['varying'] = True
if charlen:
args = (int(charlen),)
else:
args = ()
elif attype in ('interval', 'interval year to month',
'interval day to second'):
if charlen:
kwargs['precision'] = int(charlen)
args = ()
elif charlen:
args = (int(charlen),)
while True:
if attype in self.ischema_names:
coltype = self.ischema_names[attype]
break
elif attype in enums:
enum = enums[attype]
coltype = ENUM
kwargs['name'] = enum['name']
if not enum['visible']:
kwargs['schema'] = enum['schema']
args = tuple(enum['labels'])
break
elif attype in domains:
domain = domains[attype]
attype = domain['attype']
# A table can't override whether the domain is nullable.
nullable = domain['nullable']
if domain['default'] and not default:
# It can, however, override the default
# value, but can't set it to null.
default = domain['default']
continue
else:
coltype = None
break
if coltype:
coltype = coltype(*args, **kwargs)
if is_array:
coltype = self.ischema_names['_array'](coltype)
else:
util.warn("Did not recognize type '%s' of column '%s'" %
(attype, name))
coltype = sqltypes.NULLTYPE
# adjust the default value
autoincrement = False
if default is not None:
match = re.search(r"""(nextval\(')([^']+)('.*$)""", default)
if match is not None:
if issubclass(coltype._type_affinity, sqltypes.Integer):
autoincrement = True
# the default is related to a Sequence
sch = schema
if '.' not in match.group(2) and sch is not None:
# unconditionally quote the schema name. this could
# later be enhanced to obey quoting rules /
# "quote schema"
default = match.group(1) + \
('"%s"' % sch) + '.' + \
match.group(2) + match.group(3)
column_info = dict(name=name, type=coltype, nullable=nullable,
default=default, autoincrement=autoincrement)
return column_info
@reflection.cache
def get_pk_constraint(self, connection, table_name, schema=None, **kw):
table_oid = self.get_table_oid(connection, table_name, schema,
info_cache=kw.get('info_cache'))
if self.server_version_info < (8, 4):
PK_SQL = """
SELECT a.attname
FROM
pg_class t
join pg_index ix on t.oid = ix.indrelid
join pg_attribute a
on t.oid=a.attrelid AND %s
WHERE
t.oid = :table_oid and ix.indisprimary = 't'
ORDER BY a.attnum
""" % self._pg_index_any("a.attnum", "ix.indkey")
else:
# unnest() and generate_subscripts() both introduced in
# version 8.4
PK_SQL = """
SELECT a.attname
FROM pg_attribute a JOIN (
SELECT unnest(ix.indkey) attnum,
generate_subscripts(ix.indkey, 1) ord
FROM pg_index ix
WHERE ix.indrelid = :table_oid AND ix.indisprimary
) k ON a.attnum=k.attnum
WHERE a.attrelid = :table_oid
ORDER BY k.ord
"""
t = sql.text(PK_SQL, typemap={'attname': sqltypes.Unicode})
c = connection.execute(t, table_oid=table_oid)
cols = [r[0] for r in c.fetchall()]
PK_CONS_SQL = """
SELECT conname
FROM pg_catalog.pg_constraint r
WHERE r.conrelid = :table_oid AND r.contype = 'p'
ORDER BY 1
"""
t = sql.text(PK_CONS_SQL, typemap={'conname': sqltypes.Unicode})
c = connection.execute(t, table_oid=table_oid)
name = c.scalar()
return {'constrained_columns': cols, 'name': name}
@reflection.cache
def get_foreign_keys(self, connection, table_name, schema=None,
postgresql_ignore_search_path=False, **kw):
preparer = self.identifier_preparer
table_oid = self.get_table_oid(connection, table_name, schema,
info_cache=kw.get('info_cache'))
FK_SQL = """
SELECT r.conname,
pg_catalog.pg_get_constraintdef(r.oid, true) as condef,
n.nspname as conschema
FROM pg_catalog.pg_constraint r,
pg_namespace n,
pg_class c
WHERE r.conrelid = :table AND
r.contype = 'f' AND
c.oid = confrelid AND
n.oid = c.relnamespace
ORDER BY 1
"""
# http://www.postgresql.org/docs/9.0/static/sql-createtable.html
FK_REGEX = re.compile(
r'FOREIGN KEY \((.*?)\) REFERENCES (?:(.*?)\.)?(.*?)\((.*?)\)'
r'[\s]?(MATCH (FULL|PARTIAL|SIMPLE)+)?'
r'[\s]?(ON UPDATE '
r'(CASCADE|RESTRICT|NO ACTION|SET NULL|SET DEFAULT)+)?'
r'[\s]?(ON DELETE '
r'(CASCADE|RESTRICT|NO ACTION|SET NULL|SET DEFAULT)+)?'
r'[\s]?(DEFERRABLE|NOT DEFERRABLE)?'
r'[\s]?(INITIALLY (DEFERRED|IMMEDIATE)+)?'
)
t = sql.text(FK_SQL, typemap={
'conname': sqltypes.Unicode,
'condef': sqltypes.Unicode})
c = connection.execute(t, table=table_oid)
fkeys = []
for conname, condef, conschema in c.fetchall():
m = re.search(FK_REGEX, condef).groups()
constrained_columns, referred_schema, \
referred_table, referred_columns, \
_, match, _, onupdate, _, ondelete, \
deferrable, _, initially = m
if deferrable is not None:
deferrable = True if deferrable == 'DEFERRABLE' else False
constrained_columns = [preparer._unquote_identifier(x)
for x in re.split(
r'\s*,\s*', constrained_columns)]
if postgresql_ignore_search_path:
# when ignoring search path, we use the actual schema
# provided it isn't the "default" schema
if conschema != self.default_schema_name:
referred_schema = conschema
else:
referred_schema = schema
elif referred_schema:
# referred_schema is the schema that we regexp'ed from
# pg_get_constraintdef(). If the schema is in the search
# path, pg_get_constraintdef() will give us None.
referred_schema = \
preparer._unquote_identifier(referred_schema)
elif schema is not None and schema == conschema:
# If the actual schema matches the schema of the table
# we're reflecting, then we will use that.
referred_schema = schema
referred_table = preparer._unquote_identifier(referred_table)
referred_columns = [preparer._unquote_identifier(x)
for x in
re.split(r'\s*,\s', referred_columns)]
fkey_d = {
'name': conname,
'constrained_columns': constrained_columns,
'referred_schema': referred_schema,
'referred_table': referred_table,
'referred_columns': referred_columns,
'options': {
'onupdate': onupdate,
'ondelete': ondelete,
'deferrable': deferrable,
'initially': initially,
'match': match
}
}
fkeys.append(fkey_d)
return fkeys
def _pg_index_any(self, col, compare_to):
if self.server_version_info < (8, 1):
# http://www.postgresql.org/message-id/10279.1124395722@sss.pgh.pa.us
# "In CVS tip you could replace this with "attnum = ANY (indkey)".
# Unfortunately, most array support doesn't work on int2vector in
# pre-8.1 releases, so I think you're kinda stuck with the above
# for now.
# regards, tom lane"
return "(%s)" % " OR ".join(
"%s[%d] = %s" % (compare_to, ind, col)
for ind in range(0, 10)
)
else:
return "%s = ANY(%s)" % (col, compare_to)
@reflection.cache
def get_indexes(self, connection, table_name, schema, **kw):
table_oid = self.get_table_oid(connection, table_name, schema,
info_cache=kw.get('info_cache'))
# cast indkey as varchar since it's an int2vector,
# returned as a list by some drivers such as pypostgresql
if self.server_version_info < (8, 5):
IDX_SQL = """
SELECT
i.relname as relname,
ix.indisunique, ix.indexprs, ix.indpred,
a.attname, a.attnum, NULL, ix.indkey%s,
%s, am.amname
FROM
pg_class t
join pg_index ix on t.oid = ix.indrelid
join pg_class i on i.oid = ix.indexrelid
left outer join
pg_attribute a
on t.oid = a.attrelid and %s
left outer join
pg_am am
on i.relam = am.oid
WHERE
t.relkind IN ('r', 'v', 'f', 'm')
and t.oid = :table_oid
and ix.indisprimary = 'f'
ORDER BY
t.relname,
i.relname
""" % (
# version 8.3 here was based on observing the
# cast does not work in PG 8.2.4, does work in 8.3.0.
# nothing in PG changelogs regarding this.
"::varchar" if self.server_version_info >= (8, 3) else "",
"i.reloptions" if self.server_version_info >= (8, 2)
else "NULL",
self._pg_index_any("a.attnum", "ix.indkey")
)
else:
IDX_SQL = """
SELECT
i.relname as relname,
ix.indisunique, ix.indexprs, ix.indpred,
a.attname, a.attnum, c.conrelid, ix.indkey::varchar,
i.reloptions, am.amname
FROM
pg_class t
join pg_index ix on t.oid = ix.indrelid
join pg_class i on i.oid = ix.indexrelid
left outer join
pg_attribute a
on t.oid = a.attrelid and a.attnum = ANY(ix.indkey)
left outer join
pg_constraint c
on (ix.indrelid = c.conrelid and
ix.indexrelid = c.conindid and
c.contype in ('p', 'u', 'x'))
left outer join
pg_am am
on i.relam = am.oid
WHERE
t.relkind IN ('r', 'v', 'f', 'm')
and t.oid = :table_oid
and ix.indisprimary = 'f'
ORDER BY
t.relname,
i.relname
"""
t = sql.text(IDX_SQL, typemap={
'relname': sqltypes.Unicode,
'attname': sqltypes.Unicode})
c = connection.execute(t, table_oid=table_oid)
indexes = defaultdict(lambda: defaultdict(dict))
sv_idx_name = None
for row in c.fetchall():
(idx_name, unique, expr, prd, col,
col_num, conrelid, idx_key, options, amname) = row
if expr:
if idx_name != sv_idx_name:
util.warn(
"Skipped unsupported reflection of "
"expression-based index %s"
% idx_name)
sv_idx_name = idx_name
continue
if prd and not idx_name == sv_idx_name:
util.warn(
"Predicate of partial index %s ignored during reflection"
% idx_name)
sv_idx_name = idx_name
has_idx = idx_name in indexes
index = indexes[idx_name]
if col is not None:
index['cols'][col_num] = col
if not has_idx:
index['key'] = [int(k.strip()) for k in idx_key.split()]
index['unique'] = unique
if conrelid is not None:
index['duplicates_constraint'] = idx_name
if options:
index['options'] = dict(
[option.split("=") for option in options])
# it *might* be nice to include that this is 'btree' in the
# reflection info. But we don't want an Index object
# to have a ``postgresql_using`` in it that is just the
# default, so for the moment leaving this out.
if amname and amname != 'btree':
index['amname'] = amname
result = []
for name, idx in indexes.items():
entry = {
'name': name,
'unique': idx['unique'],
'column_names': [idx['cols'][i] for i in idx['key']]
}
if 'duplicates_constraint' in idx:
entry['duplicates_constraint'] = idx['duplicates_constraint']
if 'options' in idx:
entry.setdefault(
'dialect_options', {})["postgresql_with"] = idx['options']
if 'amname' in idx:
entry.setdefault(
'dialect_options', {})["postgresql_using"] = idx['amname']
result.append(entry)
return result
@reflection.cache
def get_unique_constraints(self, connection, table_name,
schema=None, **kw):
table_oid = self.get_table_oid(connection, table_name, schema,
info_cache=kw.get('info_cache'))
UNIQUE_SQL = """
SELECT
cons.conname as name,
cons.conkey as key,
a.attnum as col_num,
a.attname as col_name
FROM
pg_catalog.pg_constraint cons
join pg_attribute a
on cons.conrelid = a.attrelid AND
a.attnum = ANY(cons.conkey)
WHERE
cons.conrelid = :table_oid AND
cons.contype = 'u'
"""
t = sql.text(UNIQUE_SQL, typemap={'col_name': sqltypes.Unicode})
c = connection.execute(t, table_oid=table_oid)
uniques = defaultdict(lambda: defaultdict(dict))
for row in c.fetchall():
uc = uniques[row.name]
uc["key"] = row.key
uc["cols"][row.col_num] = row.col_name
return [
{'name': name,
'column_names': [uc["cols"][i] for i in uc["key"]]}
for name, uc in uniques.items()
]
@reflection.cache
def get_check_constraints(
self, connection, table_name, schema=None, **kw):
table_oid = self.get_table_oid(connection, table_name, schema,
info_cache=kw.get('info_cache'))
CHECK_SQL = """
SELECT
cons.conname as name,
cons.consrc as src
FROM
pg_catalog.pg_constraint cons
WHERE
cons.conrelid = :table_oid AND
cons.contype = 'c'
"""
c = connection.execute(sql.text(CHECK_SQL), table_oid=table_oid)
return [
{'name': name,
'sqltext': src[1:-1]}
for name, src in c.fetchall()
]
def _load_enums(self, connection, schema=None):
schema = schema or self.default_schema_name
if not self.supports_native_enum:
return {}
# Load data types for enums:
SQL_ENUMS = """
SELECT t.typname as "name",
-- no enum defaults in 8.4 at least
-- t.typdefault as "default",
pg_catalog.pg_type_is_visible(t.oid) as "visible",
n.nspname as "schema",
e.enumlabel as "label"
FROM pg_catalog.pg_type t
LEFT JOIN pg_catalog.pg_namespace n ON n.oid = t.typnamespace
LEFT JOIN pg_catalog.pg_enum e ON t.oid = e.enumtypid
WHERE t.typtype = 'e'
"""
if schema != '*':
SQL_ENUMS += "AND n.nspname = :schema "
# e.oid gives us label order within an enum
SQL_ENUMS += 'ORDER BY "schema", "name", e.oid'
s = sql.text(SQL_ENUMS, typemap={
'attname': sqltypes.Unicode,
'label': sqltypes.Unicode})
if schema != '*':
s = s.bindparams(schema=schema)
c = connection.execute(s)
enums = []
enum_by_name = {}
for enum in c.fetchall():
key = (enum['schema'], enum['name'])
if key in enum_by_name:
enum_by_name[key]['labels'].append(enum['label'])
else:
enum_by_name[key] = enum_rec = {
'name': enum['name'],
'schema': enum['schema'],
'visible': enum['visible'],
'labels': [enum['label']],
}
enums.append(enum_rec)
return enums
def _load_domains(self, connection):
# Load data types for domains:
SQL_DOMAINS = """
SELECT t.typname as "name",
pg_catalog.format_type(t.typbasetype, t.typtypmod) as "attype",
not t.typnotnull as "nullable",
t.typdefault as "default",
pg_catalog.pg_type_is_visible(t.oid) as "visible",
n.nspname as "schema"
FROM pg_catalog.pg_type t
LEFT JOIN pg_catalog.pg_namespace n ON n.oid = t.typnamespace
WHERE t.typtype = 'd'
"""
s = sql.text(SQL_DOMAINS, typemap={'attname': sqltypes.Unicode})
c = connection.execute(s)
domains = {}
for domain in c.fetchall():
# strip (30) from character varying(30)
attype = re.search(r'([^\(]+)', domain['attype']).group(1)
if domain['visible']:
# 'visible' just means whether or not the domain is in a
# schema that's on the search path -- or not overridden by
# a schema with higher precedence. If it's not visible,
# it will be prefixed with the schema-name when it's used.
name = domain['name']
else:
name = "%s.%s" % (domain['schema'], domain['name'])
domains[name] = {
'attype': attype,
'nullable': domain['nullable'],
'default': domain['default']
}
return domains
|