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81 lines
2.4 KiB
Plaintext
81 lines
2.4 KiB
Plaintext
# limit in subquery
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---- QUERY
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select count(*) from (select * from alltypessmall limit 10) a
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---- TYPES
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BIGINT
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---- RESULTS
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10
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====
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# order by/limit in subquery, followed by addititional selection predicate;
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# predicate is not applied in subquery
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---- QUERY
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select *
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from (select * from alltypessmall order by id limit 10) a
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where bool_col = true
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---- TYPES
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INT, BOOLEAN, TINYINT, SMALLINT, INT, BIGINT, FLOAT, DOUBLE, STRING, STRING, TIMESTAMP, INT, INT
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---- RESULTS
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0,true,0,0,0,0,0,0,'01/01/09','0',2009-01-01 00:00:00,2009,1
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2,true,2,2,2,20,2.200000047683716,20.2,'01/01/09','2',2009-01-01 00:02:00.100000000,2009,1
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4,true,4,4,4,40,4.400000095367432,40.4,'01/01/09','4',2009-01-01 00:04:00.600000000,2009,1
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6,true,6,6,6,60,6.599999904632568,60.6,'01/01/09','6',2009-01-01 00:06:00.150000000,2009,1
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8,true,8,8,8,80,8.800000190734863,80.8,'01/01/09','8',2009-01-01 00:08:00.280000000,2009,1
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====
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# order by/limit in subquery, followed by addititional selection predicate;
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# variant w/ join
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---- QUERY
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select *
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from (
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select a.* from alltypessmall a join alltypessmall using (id)
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order by a.id limit 10
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) a
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where bool_col = true
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---- TYPES
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INT, BOOLEAN, TINYINT, SMALLINT, INT, BIGINT, FLOAT, DOUBLE, STRING, STRING, TIMESTAMP, INT, INT
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---- RESULTS
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0,true,0,0,0,0,0,0,'01/01/09','0',2009-01-01 00:00:00,2009,1
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2,true,2,2,2,20,2.200000047683716,20.2,'01/01/09','2',2009-01-01 00:02:00.100000000,2009,1
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4,true,4,4,4,40,4.400000095367432,40.4,'01/01/09','4',2009-01-01 00:04:00.600000000,2009,1
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6,true,6,6,6,60,6.599999904632568,60.6,'01/01/09','6',2009-01-01 00:06:00.150000000,2009,1
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8,true,8,8,8,80,8.800000190734863,80.8,'01/01/09','8',2009-01-01 00:08:00.280000000,2009,1
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====
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---- QUERY
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# join against subquery with limit creates a merge fragment that applies the limit
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select alltypes.id, a.id
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from alltypes
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join (select id from alltypessmall order by id limit 10) a using (id)
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---- TYPES
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INT, INT
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---- RESULTS: VERIFY_IS_EQUAL_SORTED
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0,0
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1,1
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2,2
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3,3
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4,4
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5,5
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6,6
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7,7
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8,8
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9,9
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====
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---- QUERY
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# join against subquery with limit;
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# predicate pushdown is prevented in presence of order by/limit clause; variant w/ join
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select alltypes.id, a.id
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from alltypes
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join (
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select a.id, a.bool_col
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from alltypessmall a join alltypessmall using (id)
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order by a.id limit 10
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) a using (id)
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where a.bool_col = true order by a.id limit 5
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---- TYPES
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INT, INT
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---- RESULTS
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0,0
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2,2
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4,4
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6,6
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8,8
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====
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