Module read_only 

SQL commands forbidden by read-only transactions and snapshot-setting rules.

Functions

forbidden_command

The tag of a command a read-only transaction rejects, or None when the command may run: ClassifyUtilityCommandAsReadOnly rejects every utility command that changes persistent state, and ExecCheckXactReadOnly rejects a query that writes to a permanent relation.

plan_sets_transaction_snapshot

read_only_error