in reply to Re: Perl DBI and Foreign Keys
in thread Perl DBI and Foreign Keys

This may not be practical, but: do not tell the DB to create an autoincrement id for you. Instead give each new table an id YOU create and guaranteed to be unique.

That's commonly called a sequence and is often implemented in the DB server, guaranteed to deliver unique IDs under all circumstances.

Other DB servers offer only an automatic ID generator, and for that, you need to use last_insert_id in DBI (see SELECT LAST_INSERT_ID does not work).

Related: Some very common errors (or, if you want to be polite, misconceptions):

The ID generated by either of these mechanisms is JUST THAT. A unique value.


Today I will gladly share my knowledge and experience, for there are no sweeter words than "I told you so". ;-)

Replies are listed 'Best First'.
Re^3: Perl DBI and Foreign Keys
by bliako (Monsignor) on Apr 10, 2019 at 09:32 UTC

    really useful to know, thanks, bliako