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29 lines
802 B
MySQL
29 lines
802 B
MySQL
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SET optimize_move_to_prewhere = 1;
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SET enable_multiple_prewhere_read_steps = 1;
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SELECT explain
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FROM (
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EXPLAIN actions=1
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SELECT SearchPhrase, MIN(URL), MIN(Title), COUNT(*) AS c, COUNT(DISTINCT UserID)
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FROM test.hits
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WHERE Title LIKE '%Google%' AND URL NOT LIKE '%.google.%' AND SearchPhrase <> ''
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GROUP BY SearchPhrase
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ORDER BY c DESC
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LIMIT 10
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SETTINGS allow_reorder_prewhere_conditions = 0
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)
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WHERE explain like '%Prewhere filter column%';
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SELECT explain
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FROM (
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EXPLAIN actions=1
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SELECT SearchPhrase, MIN(URL), MIN(Title), COUNT(*) AS c, COUNT(DISTINCT UserID)
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FROM test.hits
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WHERE Title LIKE '%Google%' AND URL NOT LIKE '%.google.%' AND SearchPhrase <> ''
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GROUP BY SearchPhrase
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ORDER BY c DESC
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LIMIT 10
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SETTINGS allow_reorder_prewhere_conditions = 1
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)
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WHERE explain like '%Prewhere filter column%';
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