在mysql中,查询某字段为null空时,切记不可用 = null,而是 is null,不为空则是 is not null 而不是 != null select * from table where column is null;
select * from table where column is not null;
在mysql中,查询某字段为null空时,切记不可用 = null,而是 is null,不为空则是 is not null 而不是 != null select * from table where column is null;
select * from table where column is not null;