PL/PgSQL Index Usage with Trigger Variables

["Thomas F.O'Connell" <tfo@xxxxxxxxxxxx>]

I've got a question about how PL/PgSQL passes things to the planner 
based on statement logging.

E.g., I have a statement like this in PL/PgSQL:

UPDATE mytable SET mybigintcol = somevalue WHERE mybigintcol = 
NEW.myotherbigintcol;

This shows up in the logs with the NEW variable converted to unquoted 
constant data. Is PL/PgSQL smart enough to help the planner figure out 
that it can use an index on mybigintcol based on the fact that the type 
of myotherbigintcol can be discerned from the record of NEW? Or is type 
information not available as the record variable is interpolated and 
passed to the planner?

As in, should I rewrite the above statement as:

UPDATE mytable SET mybigintcol = somevalue WHERE mybigintcol = '''''' 
|| NEW.myotherbigintcol || '''''';

in order to help the planner understand that it can use an index?

-tfo

--
Thomas F. O'Connell
Co-Founder, Information Architect
Sitening, LLC
http://www.sitening.com/
110 30th Avenue North, Suite 6
Nashville, TN 37203-6320
615-260-0005


---------------------------(end of broadcast)---------------------------
TIP 9: the planner will ignore your desire to choose an index scan if your
     joining column's datatypes do not match