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23 lines
1.2 KiB
SQL
23 lines
1.2 KiB
SQL
SET optimize_use_implicit_projections = 0;
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-- the work for scalar subquery is properly accounted:
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SET max_rows_to_read = 1000000;
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SELECT 1 = (SELECT count() FROM test.hits WHERE NOT ignore(AdvEngineID)); -- { serverError TOO_MANY_ROWS }
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-- the work for subquery in IN is properly accounted:
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SET max_rows_to_read = 1000000;
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SELECT 1 IN (SELECT count() FROM test.hits WHERE NOT ignore(AdvEngineID)); -- { serverError TOO_MANY_ROWS }
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-- this query reads from the table twice:
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SET max_rows_to_read = 15000000;
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SELECT count() IN (SELECT count() FROM test.hits WHERE NOT ignore(AdvEngineID)) FROM test.hits WHERE NOT ignore(AdvEngineID); -- { serverError TOO_MANY_ROWS }
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-- the resources are properly accounted even if the subquery is evaluated in advance to facilitate the index analysis.
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-- this query is using index and filter out the second reading pass.
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SET max_rows_to_read = 1000000;
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SELECT count() FROM test.hits WHERE CounterID > (SELECT count() FROM test.hits WHERE NOT ignore(AdvEngineID)); -- { serverError TOO_MANY_ROWS }
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-- this query is using index but have to read all the data twice.
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SET max_rows_to_read = 10000000;
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SELECT count() FROM test.hits WHERE CounterID < (SELECT count() FROM test.hits WHERE NOT ignore(AdvEngineID)); -- { serverError TOO_MANY_ROWS }
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