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From Alexander Batyrshin <0x62...@gmail.com>
Subject Query optimization
Date Wed, 19 Jun 2019 14:43:33 GMT
 Hello,
We have 2 tables:

Table1 - big one (2000M+ rows):

CREATE TABLE table1 (
    pk varchar PRIMARY KEY,
    col varchar
);

Table2 - small one (300K rows):

CREATE TABLE table2 (
    pk varchar PRIMARY KEY,
    other varchar
);

Query like this work fast (~ 30sec):
SELECT table1.pk,  table1.col
FROM table1
WHERE table1.pk IN ( SELECT table2.pk FROM table2 )

But query like this work quite slow (>10min):
SELECT table1.pk
FROM table1
WHERE table1.col = ? AND table1.pk IN ( SELECT table2.pk FROM table2 )

Also query below work slow:
SELECT *
FROM (
    SELECT table1.pk,  table1.col
    FROM table1
    WHERE table1.pk IN ( SELECT table2.pk FROM table2 )
    ) AS s
WHERE s.col = ?

Is there any HINT that can optimize query?
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