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2c75a51d4f
Use (Replicated)MergeTree's metadata to do trivial count()
23 lines
663 B
SQL
23 lines
663 B
SQL
DROP TABLE IF EXISTS merge_tree;
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CREATE TABLE merge_tree (x UInt8) ENGINE = MergeTree ORDER BY x;
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INSERT INTO merge_tree SELECT 0 FROM numbers(1000000);
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SET max_threads = 4;
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SET max_rows_to_read = 1100000;
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SET merge_tree_uniform_read_distribution = 1;
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SELECT count() FROM merge_tree;
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SET merge_tree_uniform_read_distribution = 0;
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SELECT count() FROM merge_tree;
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SET max_rows_to_read = 900000;
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SET merge_tree_uniform_read_distribution = 1;
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SELECT count() FROM merge_tree WHERE not ignore(); -- { serverError 158 }
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SET merge_tree_uniform_read_distribution = 0;
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SELECT count() FROM merge_tree WHERE not ignore(); -- { serverError 158 }
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DROP TABLE merge_tree;
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