auto increment field type

[jpjsmith]

:oops:

I know this is a very simple question but I could not find (or just didn\'t look long enough) the answer. when creating a table, what is the column type for a field that is automaticaly incremented when not explcitly named in an insert statement? I plan to use this field as a primary key. Thanks for your help!! Yes, I am new to mysql!

[pallevillesen]

Normally integer....

 

sometimes BIGINT if you need a lot of records...

 

P.

[jpjsmith]

Thanks for responding. The problem is that with both the int and bigint file types, the values do not automatically increment themselves when new entries are made into the table. The values are null or 0 if declared not null in the create table statement. Is there some code to put into the sql that will make the value if the field increment?

[pallevillesen]

OK, syntax of create:

 

Here is a table for files:

CREATE TABLE files (

 ID int(15) NOT NULL auto_increment,

 path varchar(255) NOT NULL default \'\',

 filename varchar(255) NOT NULL default \'\',

 contents blob NOT NULL,

 PRIMARY KEY  (ID)

) TYPE=MyISAM;

 

 

ID is auto incrementing...

[jpjsmith]

Great! thanks for helping. this begs one question though, if i use this auto incrementing feild as a primary key, how would i retreive its value so i can use it as a foreign key in another table? thanks again!

[pallevillesen]

mysql_insert_id

 

refers to the last inserted ID in the auto_increment field.... It\'s thread specific, meaning that if 15 users are connected at the same time, mysql_insert_id will return the correct value to each user (or rather the script he is running (or she)).

 

Look in the php manual for help on this, it\'s quite easy.

 

P.

[jpjsmith]

Thanks again for your help! thats just what i needed!