This system catalog stores rewrite rules for tables and views.
Table 3-18. pg_rewrite Columns
|ev_type||char||Event type that the rule is for: '1' = SELECT, '2' = UPDATE, '3' = INSERT, '4' = DELETE|
|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)|
|is_instead||bool||True if the rule is an INSTEAD rule|
|ev_qual||text||Expression tree (in the form of a nodeToString representation) for the rule's qualifying condition|
|ev_action||text||Query tree (in the form of a nodeToString representation) for the rule's action|
Note: pg_class.relhasrules must be true if a table has any rules in this catalog.