RE: Problem with ALTER TABLE (err 1068)

Thanks Stephan for your answer but the error message would be : "ERROR 1062: Duplicate entry '255' for key 1". I tried to drop the key : "ALTER TABLE test DROP PRIMARY KEY" but I had this message : "ERROR 1075: Incorrect table definition; There can only be one auto column and it must be one auto

Problem with ALTER TABLE (err 1068)

Hello, I have a problem with the command ALTER TABLE. For example, this simple table "test" : +-+---+--+-+-++ | Field | Type | Null | Key | Default | Extra | +-+---+--+-+-+