Loadable Oracle Personality: WAS "LinuxTag wrapup" thread

Justin Clift <jc@telstra.net>

From: Justin Clift <jc@telstra.net>
To: Simon Riggs <simon@2ndquadrant.com>
Cc: Bruce Momjian <pgman@candle.pha.pa.us>, Gavin Sherry <swm@linuxworld.com.au>, Tom Lane <tgl@sss.pgh.pa.us>, Andreas Pflug <pgadmin@pse-consulting.de>, PostgreSQL Development <pgsql-hackers@postgresql.org>
Date: 2004-07-07T01:04:56Z
Lists: pgsql-hackers
Simon Riggs wrote:
<snip>
> External tool is one thing, but the loadable personality seems like a
> very good idea and worth discussing further.

Would an interesting, and maybe slightly different way of viewing a 
"loadable personality," be as a set of "rules" that can be applied to 
parser input before the parser actually gets it... and massages input 
SQL into something for the parser to understand.

I'm hugely generalising here of course, but you know how we have a 
PostgreSQL "Rules" system that rewrites queries before handing them to 
the query planner... well, would it be possible/practical to potentially 
have a "Rules" system that rewrites incoming SQL before it gets given to 
the normal parser.

Might get complicated though... we'd need a pre-parser or something.

However, having a generalised system for doing this may make it far 
easier to provide "personalities".  i.e. load a set of Oracle 8i rules, 
load a set of Oracle 9i rules, load a set of DB2 x, rules, etc.

:)

Regards and best wishes,

Justin Clift