Re: Constraint Exclusion on all tables

Simon Riggs wrote:
> On Sun, 2005-07-24 at 17:57 +0900, Tatsuo Ishii wrote:
> > It seems current CE implementation ignores UPDATE, DELETE quries. Is
> > this an intended limitation?
>
> Yes, it does not currently optimise the execution of UPDATE/DELETE
> against a parent table.
>
> This is not an intended long-term limitation and I hope to fix this
> also. The code for this is actually in a different place to the code for
> SELECT, so I need to do extra work to fix that. My priority for CE was
> to provide for the most common rolling window use cases on very large
> databases, so in those cases UPDATEs or DELETEs against large tables are
> actually fairly suicidal statements; that meant that feature had a lower
> implementation priority....but as I say, I will get to that.

Here are some new TODO items added based on this discusssion:

* Allow EXPLAIN to identify tables that were skipped because of
enable_constraint_exclusion

* Allow EXPLAIN output to be more easily processed by scripts

* Allow enable_constraint_exclusion to work for UNIONs like it does for
inheritance

* Allow enable_constraint_exclusion to work for UPDATE and DELETE queries

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