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#test for LP Bug#611379
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create table t1 (a int not null);
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insert into t1 values (1);
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create table t2 (a int not null primary key);
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insert into t2 values (10);
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explain select sum(distinct t1.a) from t1,t2 where t1.a=t2.a;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE t1 ALL NULL NULL NULL NULL 1
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1 SIMPLE t2 eq_ref PRIMARY PRIMARY 4 test.t1.a 1 Using index
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explain select * from (select sum(distinct t1.a) from t1,t2 where t1.a=t2.a)
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id select_type table type possible_keys key key_len ref rows Extra
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1 PRIMARY <derived2> system NULL NULL NULL NULL 1
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2 DERIVED t1 ALL NULL NULL NULL NULL 1
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2 DERIVED t2 eq_ref PRIMARY PRIMARY 4 test.t1.a 1 Using index
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select sum(distinct t1.a) from t1,t2 where t1.a=t2.a;
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select * from (select sum(distinct t1.a) from t1,t2 where t1.a=t2.a) as t;