creating table problem

[Anon]

I'm a mysql database newbies.I have encountered a problem when creating table.For example: I want to create a post table like that:

create table post
( ID int(5) default '0' NOT NULL auto_increment,
TopicID int(5) default '0' NOT NULL,
.....
.....
Primary key(ID));

My problem is after executing "desc post" within mysql> prompt

"Default" field show NULL but I declared it as 0 before.So would anyone tell me what's the problem about this?Thx

[dcaillouet]

There isn't a problem even though it appears as NULL. The auto_increment flag will default your ID to Max(ID) + 1 if it isn't specified. If you explicitly insert a NULL value into the ID field, it will still put in the Max(ID) + 1. If you explicitly update the ID to NULL using an Update query it will set it to zero.