~drizzle-trunk/drizzle/development

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create table t1 (a int primary key, b int, c int, unique abcindex(a,b,c), unique bcindex(b,c));
insert into t1 values (1,1,1),(2,2,2),(3,3,3),(4,4,4),(5,5,5),(6,2,3),(7,2,4),(8,2,1);
explain select * from t1 force index (abcindex) where a=2 and b=2;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	SIMPLE	t1	ref	abcindex	abcindex	9	const,const	#	Using where; Using index
select * from t1 force index (abcindex) where a=2 and b=2;
a	b	c
2	2	2
explain select a from t1 force index (bcindex) where b=2 and c>2;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	SIMPLE	t1	range	bcindex	bcindex	10	NULL	#	Using where
select a from t1 force index (bcindex) where b=2 and c>2;
a
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DROP TABLE t1;