On Tue, Sep 16, 2003 at 09:58:32AM -0400, Randy Chrismon wrote: > All this discussion about the definition of NULL and its use in > database querying has been most interesting and enlightening. I > hadn't realized I was asking such a deep question. Unfortunately, I'm > still at the stage of designing tables where I KNOW I will be loading > thousands of records that, more often than not, contain anywhere from > 10% to 50% columns where no values have been entered for whatever > reason (exporting an existing Lotus Notes database to MySQL). > Naturally, that 10-50% will never consist of precisely the same > columns from one record to the next. > > Putting aside issues about the distinctions among NULL, 0, and "", my > question is this: At the end of the day, which system is going to be > easier to export to and which will be faster (produce result sets > faster) when all the data are loaded? There are three formats for the > DDL that I can think of immediately (I'm a newbie at this stuff):
Use NULL. Disallow NULL only in columns where you know there will always be data. In the table you describe above, only the primary key will be certain to contain data. Bob Hall -- MySQL General Mailing List For list archives: http://lists.mysql.com/mysql To unsubscribe: http://lists.mysql.com/[EMAIL PROTECTED]
