Re: unique key and nulls

[Stewart Smith]

You mean a normal UNIQUE index?

create table t1 (a int unique) engine=ndb;
insert into t1 values (NULL);
insert into t1 values (NULL);
insert into t1 values (NULL);
insert into t1 values (NULL);
insert into t1 values (1);
insert into t1 values (1);


Only the last query there will produce an error.

Stewart Smith, Software Engineer - MySQL Cluster
MySQL AB, www.mysql.com

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