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39 lines
1012 B
SQL
39 lines
1012 B
SQL
DROP TABLE IF EXISTS t1;
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DROP TABLE IF EXISTS t2;
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CREATE table t1 (a UInt64, b UInt64) ENGINE = Memory;
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INSERT INTO t1 SELECT number % 2, number FROM numbers(10);
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CREATE table t2 (a UInt64) ENGINE = Memory;
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INSERT INTO t2 SELECT number % 2 FROM numbers(10);
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-- block size is always multiple of 5 because we have 5 rows for each key in right table
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-- we do not split rows corresponding to the same key
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SELECT max(bs) <= 5, b FROM (
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SELECT blockSize() as bs, * FROM t1 JOIN t2 ON t1.a = t2.a
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) GROUP BY b
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ORDER BY b
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SETTINGS max_joined_block_size_rows = 5;
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SELECT '--';
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SELECT max(bs) <= 10, b FROM (
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SELECT blockSize() as bs, * FROM t1 JOIN t2 ON t1.a = t2.a
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) GROUP BY b
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ORDER BY b
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SETTINGS max_joined_block_size_rows = 10;
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SELECT '--';
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-- parallel_hash doen't support max_joined_block_size_rows
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SET join_algorithm = 'parallel_hash';
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SELECT max(bs) > 10, b FROM (
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SELECT blockSize() as bs, * FROM t1 JOIN t2 ON t1.a = t2.a
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) GROUP BY b
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ORDER BY b
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SETTINGS max_joined_block_size_rows = 10;
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