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Merge bk-internal:/home/bk/mysql-4.1-opt
into macbook.gmz:/Users/kgeorge/mysql/work/B21180-4.1-opt
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@ -2917,3 +2917,32 @@ retailerID statusID changed
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0048 1 2006-01-06 12:37:50
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0059 1 2006-01-06 12:37:50
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drop table t1;
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create table t1(a int, primary key (a));
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insert into t1 values (10);
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create table t2 (a int primary key, b varchar(32), c int, unique key b(c, b));
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insert into t2(a, c, b) values (1,10,'359'), (2,10,'35988'), (3,10,'35989');
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explain SELECT sql_no_cache t1.a, r.a, r.b FROM t1 LEFT JOIN t2 r
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ON r.a = (SELECT t2.a FROM t2 WHERE t2.c = t1.a AND t2.b <= '359899'
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ORDER BY t2.c DESC, t2.b DESC LIMIT 1) WHERE t1.a = 10;
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id select_type table type possible_keys key key_len ref rows Extra
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1 PRIMARY t1 system PRIMARY NULL NULL NULL 1
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1 PRIMARY r const PRIMARY PRIMARY 4 const 1
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2 DEPENDENT SUBQUERY t2 range b b 38 NULL 2 Using where
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SELECT sql_no_cache t1.a, r.a, r.b FROM t1 LEFT JOIN t2 r
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ON r.a = (SELECT t2.a FROM t2 WHERE t2.c = t1.a AND t2.b <= '359899'
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ORDER BY t2.c DESC, t2.b DESC LIMIT 1) WHERE t1.a = 10;
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a a b
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10 3 35989
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explain SELECT sql_no_cache t1.a, r.a, r.b FROM t1 LEFT JOIN t2 r
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ON r.a = (SELECT t2.a FROM t2 WHERE t2.c = t1.a AND t2.b <= '359899'
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ORDER BY t2.c, t2.b LIMIT 1) WHERE t1.a = 10;
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id select_type table type possible_keys key key_len ref rows Extra
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1 PRIMARY t1 system PRIMARY NULL NULL NULL 1
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1 PRIMARY r const PRIMARY PRIMARY 4 const 1
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2 DEPENDENT SUBQUERY t2 range b b 38 NULL 2 Using where
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SELECT sql_no_cache t1.a, r.a, r.b FROM t1 LEFT JOIN t2 r
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ON r.a = (SELECT t2.a FROM t2 WHERE t2.c = t1.a AND t2.b <= '359899'
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ORDER BY t2.c, t2.b LIMIT 1) WHERE t1.a = 10;
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a a b
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10 1 359
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drop table t1,t2;
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