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Diffstat (limited to 'src/backend/utils/time/snapmgr.c')
| -rw-r--r-- | src/backend/utils/time/snapmgr.c | 26 |
1 files changed, 26 insertions, 0 deletions
diff --git a/src/backend/utils/time/snapmgr.c b/src/backend/utils/time/snapmgr.c index a0b703a5195..a0b81bf1549 100644 --- a/src/backend/utils/time/snapmgr.c +++ b/src/backend/utils/time/snapmgr.c @@ -1625,6 +1625,32 @@ ThereAreNoPriorRegisteredSnapshots(void) return false; } +/* + * HaveRegisteredOrActiveSnapshots + * Is there any registered or active snapshot? + * + * NB: Unless pushed or active, the cached catalog snapshot will not cause + * this function to return true. That allows this function to be used in + * checks enforcing a longer-lived snapshot. + */ +bool +HaveRegisteredOrActiveSnapshot(void) +{ + if (ActiveSnapshot != NULL) + return true; + + /* + * The catalog snapshot is in RegisteredSnapshots when valid, but can be + * removed at any time due to invalidation processing. If explicitly + * registered more than one snapshot has to be in RegisteredSnapshots. + */ + if (pairingheap_is_empty(&RegisteredSnapshots) || + !pairingheap_is_singular(&RegisteredSnapshots)) + return false; + + return CatalogSnapshot == NULL; +} + /* * Return a timestamp that is exactly on a minute boundary. |