Re: Get the name of the target Relation from Query struct?

On 5 April 2018 at 22:34, Ernst-Georg Schmid
<ernst-georg(dot)schmid(at)bayer(dot)com> wrote:
> I want to get the target Relation name for a UPDATE / INSERT / DELETE in a planner_hook. Do I understand struct Query correctly that:
>
> Query->resultRelation will be the index into Query->rtable to give me the target Relation?

Yes

> And if yes, what would rtable give me as list entry? An OID or a Relation or something else?

The list_nth(query->rtable, query->resultRelation) will give you a
RangeTblEntry which has a property called relid, which is the
Relation's OID as per pg_class.oid.

If you want the relation name from the OID then you'll need something
like get_rel_name().

You'll probably also want to check the query->commandType to ensure
the command is one that will actually have a valid resultRelation.

--
David Rowley http://www.2ndQuadrant.com/
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