From: Paul DuBois [mailto:[EMAIL PROTECTED] > At 21:09 +0200 6/16/03, Fernando Martins wrote: > >In AUTO_INCREMENT fields, inserting a 0 into the field requests a new > >sequence number. > > > >Is it possible to turn off this behaviour? (without messing with > the code, > >of course) > > No. > > > > >Using NULL to get the next sequence number is good enough for me > and I use > >quite a lot 0 for special purposes (default record values,...) > > That is an unsupported use of an AUTO_INCREMENT column, which is intended > to hold only positive integer values. Not negative values, and not zero.
Hmm, the manual is not very consistent with that: "AUTO_INCREMENT will not work with negative numbers."; "It’s possible to create a row where the AUTO_INCREMENT column is 0 by explicitly setting the column to 0 with an UPDATE statement)"; and some examples using UNSIGNED. > > (You will find, for example, that if you run CHECK TABLE on your table, > it will complain about 0 values in an AUTO_INCREMENT column. Also, > dumping and restoring the table will change your zero values.) > Damn! Glad you told me that! I had missed it in the manual. By dumping, you mean BACKUP, mysqldump, SELECT * INTO OUTFILE or all of them? The manual is also not explicit on that. I've to say (not to complain) this looks wrong. Definitely unexpected. (A dump/restore modifying data) The manual recomends using NULL over 0 as the magic value to use to get the sequence number. I had some hopes this could mean some way to cancel the magic effect of 0 (hence my post) or some future plans to drop it. Any chances? Thanks, Fernando -- MySQL General Mailing List For list archives: http://lists.mysql.com/mysql To unsubscribe: http://lists.mysql.com/[EMAIL PROTECTED]
