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35 lines
1.1 KiB
SQL
35 lines
1.1 KiB
SQL
DROP TABLE IF EXISTS t_sparse_columns_clear;
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CREATE TABLE t_sparse_columns_clear (arr Array(UInt64), v UInt64)
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ENGINE = MergeTree ORDER BY tuple()
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SETTINGS
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ratio_of_defaults_for_sparse_serialization = 0.9,
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min_bytes_for_wide_part=0;
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INSERT INTO t_sparse_columns_clear SELECT [number], 0 FROM numbers(1000);
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SELECT column, serialization_kind FROM system.parts_columns
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WHERE database = currentDatabase() AND table = 't_sparse_columns_clear' AND active
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ORDER BY column;
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SET mutations_sync = 2;
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SET alter_sync = 2;
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ALTER TABLE t_sparse_columns_clear CLEAR COLUMN v;
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SELECT column, serialization_kind FROM system.parts_columns
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WHERE database = currentDatabase() AND table = 't_sparse_columns_clear' AND active
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ORDER BY column;
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OPTIMIZE TABLE t_sparse_columns_clear FINAL;
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SELECT column, serialization_kind FROM system.parts_columns
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WHERE database = currentDatabase() AND table = 't_sparse_columns_clear' AND active
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ORDER BY column;
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DROP TABLE t_sparse_columns_clear SYNC;
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SYSTEM FLUSH LOGS;
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SELECT count(), groupArray(message) FROM system.text_log WHERE logger_name LIKE '%' || currentDatabase() || '.t_sparse_columns_clear' || '%' AND level = 'Error';
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