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21 lines
637 B
MySQL
21 lines
637 B
MySQL
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DROP TABLE IF EXISTS t_sparse_distinct;
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CREATE TABLE t_sparse_distinct (id UInt32, v UInt64)
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ENGINE = MergeTree
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ORDER BY id
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SETTINGS ratio_of_defaults_for_sparse_serialization = 0.9;
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SYSTEM STOP MERGES t_sparse_distinct;
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INSERT INTO t_sparse_distinct SELECT number, number % 5 FROM numbers(100000);
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INSERT INTO t_sparse_distinct SELECT number, number % 100 = 0 FROM numbers(100000);
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SELECT name, column, serialization_kind
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FROM system.parts_columns
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WHERE table = 't_sparse_distinct' AND database = currentDatabase() AND column = 'v'
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ORDER BY name;
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SELECT DISTINCT v FROM t_sparse_distinct ORDER BY v;
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DROP TABLE t_sparse_distinct;
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