1 create table t1 ( f1 int, f2 int);
2 insert into t1 values(1, 1);
3 insert into t1 values(1, 2);
4 insert into t1 values(5, 5);
5 insert into t1 values(2, 1);
6 insert into t1 values(2, 2);
7 echo create index ind on t1(f1)unique;
8 create index ind on t1(f1) unique;
