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48 lines
1.3 KiB
MySQL
48 lines
1.3 KiB
MySQL
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DROP TABLE IF EXISTS t1;
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SET allow_experimental_statistic = 1;
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SET allow_statistic_optimize = 1;
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CREATE TABLE t1
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(
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a Int64,
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b Float64,
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pk String,
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STATISTIC a TYPE tdigest,
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STATISTIC b TYPE tdigest
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) Engine = MergeTree() ORDER BY pk;
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SHOW CREATE TABLE t1;
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INSERT INTO t1 select number, -number, generateUUIDv4() FROM system.numbers LIMIT 10000;
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SELECT 'After insert';
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EXPLAIN SYNTAX SELECT count(*) FROM t1 WHERE b < 10 and a < 10;
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SELECT count(*) FROM t1 WHERE b < 10 and a < 10;
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ALTER TABLE t1 DROP STATISTIC a TYPE tdigest;
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ALTER TABLE t1 DROP STATISTIC b TYPE tdigest;
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SELECT 'After drop statistic';
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EXPLAIN SYNTAX SELECT count(*) FROM t1 WHERE b < 10 and a < 10;
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SELECT count(*) FROM t1 WHERE b < 10 and a < 10;
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ALTER TABLE t1 ADD STATISTIC a TYPE tdigest;
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ALTER TABLE t1 ADD STATISTIC b TYPE tdigest;
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ALTER TABLE t1 MATERIALIZE STATISTIC a TYPE tdigest;
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ALTER TABLE t1 MATERIALIZE STATISTIC b TYPE tdigest;
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INSERT INTO t1 select number, -number, generateUUIDv4() FROM system.numbers LIMIT 10000;
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SELECT 'After materialize statistic';
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EXPLAIN SYNTAX SELECT count(*) FROM t1 WHERE b < 10 and a < 10;
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SELECT count(*) FROM t1 WHERE b < 10 and a < 10;
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OPTIMIZE TABLE t1 FINAL;
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SELECT 'After merge';
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EXPLAIN SYNTAX SELECT count(*) FROM t1 WHERE b < 10 and a < 10;
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SELECT count(*) FROM t1 WHERE b < 10 and a < 10;
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DROP TABLE IF EXISTS t1;
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