NOT NULLs With Default
I'm cleaning up a database but I see this all over the MySQL world. I understand that having defaults speeds things up. But what I don't understand is why someone would make a field NOT NULL and then put a null default in it? This makes no sense to me at all. Is this the fault of using phpMyAdmin to create tables?
Here's a sample:
CREATE TABLE `listnames` (
`id` int(11) NOT NULL auto_increment,
`list_name` char(30) NOT NULL default '',
`display_name` char(100) NOT NULL default '',
`active` char(3) NOT NULL default '',
`last_modified` timestamp(14) NOT NULL,
UNIQUE KEY `id` (`id`)
)
Ok, so you don't want NULLs in your data but there is no default. It's very likely that the data will be wildly differently. So setting a default makes no sense -- or does it?
I don't want to drop the default '' if it makes sense & I'm just not getting it.
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