drop table if exists t1;CREATE TABLE t1 (a int, unique (a), b int not null, unique(b), c int not null, index(c));replace into t1 values (1,1,1),(2,2,2),(3,1,3);select * from t1;a b c3 1 32 2 2check table t1;Table Op Msg_type Msg_texttest.t1 check status OKdrop table t1;