Sorry for the multiple replies-to-self, but this seemed worth
specifically noting: the expansion also results in multiple calls to
tuple-returning functions, even functions marked VOLATILE. For example:
CREATE OR REPLACE FUNCTION expandtest(INTEGER) RETURNS test AS $$
DECLARE
rec test;
BEGIN
> This may be simplified to the comparison between these two queries:
... or even further into:
CREATE TYPE test AS ( a integer, b integer, c integer, d integer );
EXPLAIN SELECT ((SELECT ROW(1,1,1,1)::test)::test);
EXPLAIN SELECT ((SELECT ROW(1,1,1,1)::test)::test).*;
craig=# EXPLAIN SELECT (
On 13/11/2009 7:25 PM, Oleg Serov wrote:
> EXPLAIN ANALYZE SELECT ((SELECT tmp::test FROM (SELECT * FROM test
> LIMIT 1) tmp)::test).*;
This may be simplified to the comparison between these two queries:
SELECT ((SELECT test FROM test LIMIT 1)::test);
SELECT ((SELECT test FROM test LIMIT 1)::tes
SQL:
CREATE TABLE test (id BIGINT, id2 BIGINT, id3 BIGINT, id4 BIGINT);
INSERT INTO test SELECT i, i, i, i FROM generate_series(0, 9) i;
EXPLAIN ANALYZE SELECT ((SELECT tmp::test FROM (SELECT * FROM test
LIMIT 1) tmp)::test).*;
WILL:
QUERY PLAN
Result (cost=0.11..0.12 rows=1 width=0) (actual time
