1. 23 Mar, 2007 10 commits
  2. 22 Mar, 2007 15 commits
  3. 21 Mar, 2007 9 commits
  4. 20 Mar, 2007 5 commits
  5. 19 Mar, 2007 1 commit
    • Jan Wieck's avatar
      Changes pg_trigger and extend pg_rewrite in order to allow triggers and · 0fe16500
      Jan Wieck authored
      rules to be defined with different, per session controllable, behaviors
      for replication purposes.
      
      This will allow replication systems like Slony-I and, as has been stated
      on pgsql-hackers, other products to control the firing mechanism of
      triggers and rewrite rules without modifying the system catalog directly.
      
      The firing mechanisms are controlled by a new superuser-only GUC
      variable, session_replication_role, together with a change to
      pg_trigger.tgenabled and a new column pg_rewrite.ev_enabled. Both
      columns are a single char data type now (tgenabled was a bool before).
      The possible values in these attributes are:
      
           'O' - Trigger/Rule fires when session_replication_role is "origin"
                 (default) or "local". This is the default behavior.
      
           'D' - Trigger/Rule is disabled and fires never
      
           'A' - Trigger/Rule fires always regardless of the setting of
                 session_replication_role
      
           'R' - Trigger/Rule fires when session_replication_role is "replica"
      
      The GUC variable can only be changed as long as the system does not have
      any cached query plans. This will prevent changing the session role and
      accidentally executing stored procedures or functions that have plans
      cached that expand to the wrong query set due to differences in the rule
      firing semantics.
      
      The SQL syntax for changing a triggers/rules firing semantics is
      
           ALTER TABLE <tabname> <when> TRIGGER|RULE <name>;
      
           <when> ::= ENABLE | ENABLE ALWAYS | ENABLE REPLICA | DISABLE
      
      psql's \d command as well as pg_dump are extended in a backward
      compatible fashion.
      
      Jan
      0fe16500