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Diffstat (limited to 'src/backend/access/transam/xact.c')
| -rw-r--r-- | src/backend/access/transam/xact.c | 26 |
1 files changed, 26 insertions, 0 deletions
diff --git a/src/backend/access/transam/xact.c b/src/backend/access/transam/xact.c index c83aa16f2ce..6395a9b2408 100644 --- a/src/backend/access/transam/xact.c +++ b/src/backend/access/transam/xact.c @@ -1015,6 +1015,32 @@ IsInParallelMode(void) } /* + * PrepareParallelModePlanExec + * + * Prepare for entering parallel mode plan execution, based on command-type. + */ +void +PrepareParallelModePlanExec(CmdType commandType) +{ + if (IsModifySupportedInParallelMode(commandType)) + { + Assert(!IsInParallelMode()); + + /* + * Prepare for entering parallel mode by assigning a TransactionId. + * Failure to do this now would result in heap_insert() subsequently + * attempting to assign a TransactionId whilst in parallel-mode, which + * is not allowed. + * + * This approach has a disadvantage in that if the underlying SELECT + * does not return any rows, then the TransactionId is not used, + * however that shouldn't happen in practice in many cases. + */ + (void) GetCurrentTransactionId(); + } +} + +/* * CommandCounterIncrement */ void |