|
68 | 68 | #include"utils/syscache.h" |
69 | 69 |
|
70 | 70 |
|
| 71 | +/* |
| 72 | + * We must skip "overhead" operations that involve database access when the |
| 73 | + * cached plan's subject statement is a transaction control command. |
| 74 | + */ |
| 75 | +#defineIsTransactionStmtPlan(plansource) \ |
| 76 | +((plansource)->raw_parse_tree && \ |
| 77 | + IsA((plansource)->raw_parse_tree, TransactionStmt)) |
| 78 | + |
71 | 79 | /* |
72 | 80 | * This is the head of the backend's list of "saved" CachedPlanSources (i.e., |
73 | 81 | * those that are in long-lived storage and are examined for sinval events). |
@@ -352,23 +360,27 @@ CompleteCachedPlan(CachedPlanSource *plansource, |
352 | 360 | plansource->query_context=querytree_context; |
353 | 361 | plansource->query_list=querytree_list; |
354 | 362 |
|
355 | | -/* |
356 | | - * Use the planner machinery to extract dependencies. Data is saved in |
357 | | - * query_context. (We assume that not a lot of extra cruft is created by |
358 | | - * this call.) We can skip this for one-shot plans. |
359 | | - */ |
360 | | -if (!plansource->is_oneshot) |
| 363 | +if (!plansource->is_oneshot&& !IsTransactionStmtPlan(plansource)) |
| 364 | +{ |
| 365 | +/* |
| 366 | + * Use the planner machinery to extract dependencies. Data is saved |
| 367 | + * in query_context. (We assume that not a lot of extra cruft is |
| 368 | + * created by this call.) We can skip this for one-shot plans, and |
| 369 | + * transaction control commands have no such dependencies anyway. |
| 370 | + */ |
361 | 371 | extract_query_dependencies((Node*)querytree_list, |
362 | 372 | &plansource->relationOids, |
363 | 373 | &plansource->invalItems); |
364 | 374 |
|
365 | | -/* |
366 | | - * Also save the current search_path in the query_context. (This should |
367 | | - * not generate much extra cruft either, since almost certainly the path |
368 | | - * is already valid.) Again, don't really need it for one-shot plans. |
369 | | - */ |
370 | | -if (!plansource->is_oneshot) |
| 375 | +/* |
| 376 | + * Also save the current search_path in the query_context. (This |
| 377 | + * should not generate much extra cruft either, since almost certainly |
| 378 | + * the path is already valid.) Again, we don't really need this for |
| 379 | + * one-shot plans; and we *must* skip this for transaction control |
| 380 | + * commands, because this could result in catalog accesses. |
| 381 | + */ |
371 | 382 | plansource->search_path=GetOverrideSearchPath(querytree_context); |
| 383 | +} |
372 | 384 |
|
373 | 385 | /* |
374 | 386 | * Save the final parameter types (or other parameter specification data) |
@@ -542,9 +554,11 @@ RevalidateCachedQuery(CachedPlanSource *plansource) |
542 | 554 | /* |
543 | 555 | * For one-shot plans, we do not support revalidation checking; it's |
544 | 556 | * assumed the query is parsed, planned, and executed in one transaction, |
545 | | - * so that no lock re-acquisition is necessary. |
| 557 | + * so that no lock re-acquisition is necessary. Also, there is never |
| 558 | + * any need to revalidate plans for transaction control commands (and |
| 559 | + * we mustn't risk any catalog accesses when handling those). |
546 | 560 | */ |
547 | | -if (plansource->is_oneshot) |
| 561 | +if (plansource->is_oneshot||IsTransactionStmtPlan(plansource)) |
548 | 562 | { |
549 | 563 | Assert(plansource->is_valid); |
550 | 564 | returnNIL; |
@@ -967,6 +981,9 @@ choose_custom_plan(CachedPlanSource *plansource, ParamListInfo boundParams) |
967 | 981 | /* Otherwise, never any point in a custom plan if there's no parameters */ |
968 | 982 | if (boundParams==NULL) |
969 | 983 | return false; |
| 984 | +/* ... nor for transaction control statements */ |
| 985 | +if (IsTransactionStmtPlan(plansource)) |
| 986 | +return false; |
970 | 987 |
|
971 | 988 | /* See if caller wants to force the decision */ |
972 | 989 | if (plansource->cursor_options&CURSOR_OPT_GENERIC_PLAN) |
@@ -1622,6 +1639,10 @@ PlanCacheRelCallback(Datum arg, Oid relid) |
1622 | 1639 | if (!plansource->is_valid) |
1623 | 1640 | continue; |
1624 | 1641 |
|
| 1642 | +/* Never invalidate transaction control commands */ |
| 1643 | +if (IsTransactionStmtPlan(plansource)) |
| 1644 | +continue; |
| 1645 | + |
1625 | 1646 | /* |
1626 | 1647 | * Check the dependency list for the rewritten querytree. |
1627 | 1648 | */ |
@@ -1686,6 +1707,10 @@ PlanCacheFuncCallback(Datum arg, int cacheid, uint32 hashvalue) |
1686 | 1707 | if (!plansource->is_valid) |
1687 | 1708 | continue; |
1688 | 1709 |
|
| 1710 | +/* Never invalidate transaction control commands */ |
| 1711 | +if (IsTransactionStmtPlan(plansource)) |
| 1712 | +continue; |
| 1713 | + |
1689 | 1714 | /* |
1690 | 1715 | * Check the dependency list for the rewritten querytree. |
1691 | 1716 | */ |
@@ -1775,6 +1800,11 @@ ResetPlanCache(void) |
1775 | 1800 | * We *must not* mark transaction control statements as invalid, |
1776 | 1801 | * particularly not ROLLBACK, because they may need to be executed in |
1777 | 1802 | * aborted transactions when we can't revalidate them (cf bug #5269). |
| 1803 | + */ |
| 1804 | +if (IsTransactionStmtPlan(plansource)) |
| 1805 | +continue; |
| 1806 | + |
| 1807 | +/* |
1778 | 1808 | * In general there is no point in invalidating utility statements |
1779 | 1809 | * since they have no plans anyway. So invalidate it only if it |
1780 | 1810 | * contains at least one non-utility statement, or contains a utility |
|