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Use OFFSET 0 instead of ORDER BY to stop subquery pullup

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b762fed64 recently changed this test to prevent subquery pullup to allow
us to test Memoize with lateral_vars.  As pointed out by Tom Lane, OFFSET
0 is our standard way of preventing subquery pullups, so do it that way
instead.

Discussion: https://postgr.es/m/2144818.1674517061@sss.pgh.pa.us
Backpatch-through: 14, same as b762fed64
This commit is contained in:
David Rowley 2023-01-24 13:50:11 +13:00
parent bcec08907e
commit 0765b2f8f6
2 changed files with 4 additions and 4 deletions
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4
src/test/regress/expected/memoize.out
View File

@ -64,7 +64,7 @@ WHERE t2.unique1 < 1000;
SELECT explain_memoize('
SELECT COUNT(*),AVG(t2.unique1) FROM tenk1 t1,
LATERAL (SELECT t2.unique1 FROM tenk1 t2
WHERE t1.twenty = t2.unique1 ORDER BY 1) t2
WHERE t1.twenty = t2.unique1 OFFSET 0) t2
WHERE t1.unique1 < 1000;', false);
explain_memoize
-------------------------------------------------------------------------------------------
@ -85,7 +85,7 @@ WHERE t1.unique1 < 1000;', false);
-- And check we get the expected results.
SELECT COUNT(*),AVG(t2.unique1) FROM tenk1 t1,
LATERAL (SELECT t2.unique1 FROM tenk1 t2
WHERE t1.twenty = t2.unique1 ORDER BY 1) t2
WHERE t1.twenty = t2.unique1 OFFSET 0) t2
WHERE t1.unique1 < 1000;
count | avg
-------+--------------------

4
src/test/regress/sql/memoize.sql
View File

@ -48,13 +48,13 @@ WHERE t2.unique1 < 1000;
SELECT explain_memoize('
SELECT COUNT(*),AVG(t2.unique1) FROM tenk1 t1,
LATERAL (SELECT t2.unique1 FROM tenk1 t2
WHERE t1.twenty = t2.unique1 ORDER BY 1) t2
WHERE t1.twenty = t2.unique1 OFFSET 0) t2
WHERE t1.unique1 < 1000;', false);
-- And check we get the expected results.
SELECT COUNT(*),AVG(t2.unique1) FROM tenk1 t1,
LATERAL (SELECT t2.unique1 FROM tenk1 t2
WHERE t1.twenty = t2.unique1 ORDER BY 1) t2
WHERE t1.twenty = t2.unique1 OFFSET 0) t2
WHERE t1.unique1 < 1000;
-- Reduce work_mem so that we see some cache evictions