I looked at the plan with the explaination of the query (see pag 9 of http://www.postgresql.org/files/developer/internalpics.pdf for an example) and I found a way to take varattno from a Query structure using FromExpr jointree and casting in the right way the list and node to arrive at the Var structure.
From: carla.celiberti@hotmail.it To: pgsql-hackers@postgresql.org Subject: Taking the "varattno" in "args" (where part of a query) Date: Wed, 8 May 2013 20:38:01 +0200
Hi everyone,
I'm working on a project and one of my task is trying to take the "where" part of the queries.
I'm programming inside the function "exec_simple_query" in "postgres.c".
I searched inside the source code and how I've understood I need to take the "varattno" in "args" in "qpqual", is it right?
If yes, how do I have to save it in order to have it in that function?
If no, what is the easiest way to take it?
Example:
For a query: select firstname from friend where age=33
The attributes of the table friends are: firstname, lastname, city, state, age
I need to have the number 5 because "age" is the fifth attribute of "friend".
