how to delimit a size of a table

hi

how to delimit a size of a table?
i'd like to have only 100 records

should i delete one with the lowest id
and run update which decrease others id by 1
and the insert new one?

i think that will be very hard to run many task like that
any ideas ?

You want to have 100 records all the time or just delete old ones from time to time?

In the first case just do
DELETE FROM table where id=min(id);
and then insert the new record.

In the second case:
DELETE FROM table where id<min(id)+100;
And just run the statement from time to time - put it into a file and schedule the program to run every 10 minutes.

Another sugestion could be to use triger to automaticaly delete oldest row when new row will be inserted and when there is already 100 records in table.

I've seen triggers mentioned in a couple threads lately. MySQL does not have stored procedures of any kind - they are slated to be implemented sometime around version 5.0. Triggers are scheduled for version 5.1. See this page for details.

Oh, then sorry. I have never worked with mySQL.