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30 lines
1.3 KiB
SQL
30 lines
1.3 KiB
SQL
DROP TABLE IF EXISTS t_optimize_equal_ranges;
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CREATE TABLE t_optimize_equal_ranges (a UInt64, b String, c UInt64) ENGINE = MergeTree ORDER BY a;
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SET max_block_size = 1024;
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SET max_bytes_before_external_group_by = 0;
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SET optimize_aggregation_in_order = 0;
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SET optimize_use_projections = 0;
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INSERT INTO t_optimize_equal_ranges SELECT 0, toString(number), number FROM numbers(30000);
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INSERT INTO t_optimize_equal_ranges SELECT 1, toString(number), number FROM numbers(30000);
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INSERT INTO t_optimize_equal_ranges SELECT 2, toString(number), number FROM numbers(30000);
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SELECT a, uniqExact(b) FROM t_optimize_equal_ranges GROUP BY a ORDER BY a SETTINGS max_threads = 16;
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SELECT a, uniqExact(b) FROM t_optimize_equal_ranges GROUP BY a ORDER BY a SETTINGS max_threads = 1;
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SELECT a, sum(c) FROM t_optimize_equal_ranges GROUP BY a ORDER BY a SETTINGS max_threads = 16;
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SELECT a, sum(c) FROM t_optimize_equal_ranges GROUP BY a ORDER BY a SETTINGS max_threads = 1;
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SYSTEM FLUSH LOGS;
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SELECT
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used_aggregate_functions[1] AS func,
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Settings['max_threads'] AS threads,
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ProfileEvents['AggregationOptimizedEqualRangesOfKeys'] > 0
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FROM system.query_log
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WHERE type = 'QueryFinish' AND current_database = currentDatabase() AND query LIKE '%SELECT%FROM%t_optimize_equal_ranges%'
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ORDER BY func, threads;
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DROP TABLE t_optimize_equal_ranges;
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