A couple of comments in addition to what others have mentioned:

Your check_exists() sub exposes a race condition in a multi-user system, as two users selecting the same username at approximately the same time could both get the OK to use that username, with the second one getting an error on the insert (assuming you have a unique index or constraint on the "nick" column.

In general I prefer to let the database find out if a value is already taken as part of the insert operation. To do this you need to have a unique index on the column ("nick" in this case), and check for unique key violations during the insert.

I don't know MySQL, but you should be able to create indexes on column(s) beside the primary key column. In any case if a column is supposed to be unique then you should have a constraint that enforces this (that constraint in this case would be a unique index).

Michael

In reply to Re: perl (mysql) question... by mpeppler
in thread perl (mysql) question... by kiat

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