diff options
Diffstat (limited to 'src/backend/commands/variable.c')
| -rw-r--r-- | src/backend/commands/variable.c | 13 |
1 files changed, 11 insertions, 2 deletions
diff --git a/src/backend/commands/variable.c b/src/backend/commands/variable.c index 8550869db3d..3eb911c5cc5 100644 --- a/src/backend/commands/variable.c +++ b/src/backend/commands/variable.c @@ -569,11 +569,16 @@ show_log_timezone(void) * read-only may be changed to read-write only when in a top-level transaction * that has not yet taken an initial snapshot. Can't do it in a hot standby * slave, either. + * + * If we are not in a transaction at all, just allow the change; it means + * nothing since XactReadOnly will be reset by the next StartTransaction(). + * The IsTransactionState() test protects us against trying to check + * RecoveryInProgress() in contexts where shared memory is not accessible. */ bool check_transaction_read_only(bool *newval, void **extra, GucSource source) { - if (*newval == false && XactReadOnly) + if (*newval == false && XactReadOnly && IsTransactionState()) { /* Can't go to r/w mode inside a r/o transaction */ if (IsSubTransaction()) @@ -592,6 +597,7 @@ check_transaction_read_only(bool *newval, void **extra, GucSource source) /* Can't go to r/w mode while recovery is still active */ if (RecoveryInProgress()) { + GUC_check_errcode(ERRCODE_FEATURE_NOT_SUPPORTED); GUC_check_errmsg("cannot set transaction read-write mode during recovery"); return false; } @@ -605,6 +611,8 @@ check_transaction_read_only(bool *newval, void **extra, GucSource source) * * We allow idempotent changes at any time, but otherwise this can only be * changed in a toplevel transaction that has not yet taken a snapshot. + * + * As in check_transaction_read_only, allow it if not inside a transaction. */ bool check_XactIsoLevel(char **newval, void **extra, GucSource source) @@ -634,7 +642,7 @@ check_XactIsoLevel(char **newval, void **extra, GucSource source) else return false; - if (newXactIsoLevel != XactIsoLevel) + if (newXactIsoLevel != XactIsoLevel && IsTransactionState()) { if (FirstSnapshotSet) { @@ -652,6 +660,7 @@ check_XactIsoLevel(char **newval, void **extra, GucSource source) /* Can't go to serializable mode while recovery is still active */ if (newXactIsoLevel == XACT_SERIALIZABLE && RecoveryInProgress()) { + GUC_check_errcode(ERRCODE_FEATURE_NOT_SUPPORTED); GUC_check_errmsg("cannot use serializable mode in a hot standby"); GUC_check_errhint("You can use REPEATABLE READ instead."); return false; |