The catalog pg_rewrite stores rewrite rules for tables and views.
Tabella 45.32. pg_rewrite Columns
|ev_class||oid||pg_class.oid||The table this rule is for|
|ev_attr||int2||The column this rule is for (currently, always zero to indicate the whole table)|
|ev_type||char||Event type that the rule is for: 1 = SELECT, 2 = UPDATE, 3 = INSERT, 4 = DELETE|
|ev_enabled||char||Controls in which session_replication_role modes the rule fires. O = rule fires in «origin» and «local» modes, D = rule is disabled, R = rule fires in «replica» mode, A = rule fires always.|
|is_instead||bool||True if the rule is an INSTEAD rule|
|ev_qual||pg_node_tree||Expression tree (in the form of a nodeToString() representation) for the rule's qualifying condition|
|ev_action||pg_node_tree||Query tree (in the form of a nodeToString() representation) for the rule's action|
pg_class.relhasrules must be true if a table has any rules in this catalog.