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58 lines
1.5 KiB
SQL
58 lines
1.5 KiB
SQL
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 Float64 STATISTIC(tdigest),
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b Int64 STATISTIC(tdigest),
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pk String,
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) Engine = MergeTree() ORDER BY pk
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SETTINGS min_bytes_for_wide_part = 0;
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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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SELECT count(*) FROM t1 WHERE b < NULL and a < '10';
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ALTER TABLE t1 DROP STATISTIC a, 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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SHOW CREATE TABLE t1;
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ALTER TABLE t1 ADD STATISTIC a, b TYPE tdigest;
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SELECT 'After add statistic';
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SHOW CREATE TABLE t1;
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ALTER TABLE t1 MATERIALIZE STATISTIC a, 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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ALTER TABLE t1 RENAME COLUMN b TO c;
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SHOW CREATE TABLE t1;
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SELECT 'After rename';
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EXPLAIN SYNTAX SELECT count(*) FROM t1 WHERE c < 10 and a < 10;
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SELECT count(*) FROM t1 WHERE c < 10 and a < 10;
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DROP TABLE IF EXISTS t1;
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