That's just what I wanted to do. 1 primary key made up with multiple fields. In my case I will be a Date Field for Transaction Date and a Integer field for StoreNumber.
Thanks a lot for your advice, guys. :oD -----Original Message----- From: Mark V [mailto:[EMAIL PROTECTED] Sent: Monday, October 20, 2003 2:34 PM To: [EMAIL PROTECTED] Subject: Re: Newbie - Primary Keys Good points Patrick. Thanks for the follow-up :-) --- Patrick Shoaf <[EMAIL PROTECTED]> wrote: --------------------------------- Mark is correct, you can define only 1 Primary Key, but the primary keycan be made up of multiple fields. Example: CREATE TABLE test (item_code char(5) NOT NULL,item_color char(5) NOTNULL, data varchar(255), PRIMARY KEY (ITEM_CODE,ITEM_COLOR)); This would allow multiple entries for an item_code and multiple entriesfor item_color, but only 1 entry for a combination. example item_code | item_color | data --------------------------- hammer | red | my favorite hammer | blue |nice color nail |red | ugly item nail | green | nice combination with red hammer name |blue | good with red hammer With the option below you can only have 1 hammer, and only 1 nail in theid1 field. You need to decide do you need multiple indexes, or do you need 1 indexwith multiple data fields. At 02:07 PM 10/20/2003, Mark V wrote: Hi Carlos, You can't have 2 primary keys. A table can only have one primary key. You can, however, also define a Unique key, and if you set it up such that it is not null, it will act much like a prmary key: CREATE TABLE test ( id1 INT UNSIGNED NOT NULL, PRIMARY KEY (id1), id2 INT UNSIGNED NOT NULL, UNIQUE KEY (id2), data VARCHAR(25) ); Hope that helps, Mark --- Carlos Vazquez <[EMAIL PROTECTED]> wrote: > Hi all! > > Just wanted to know how do I create a table with two > primary keys. > > Thanks a lot! > > __________________________________ Do you Yahoo!? The New Yahoo! Shopping - with improved product search http://shopping.yahoo.com -- MySQL General Mailing List For list archives: http://lists.mysql.com/mysql To unsubscribe: http://lists.mysql.com/[EMAIL PROTECTED] -- MySQL General Mailing List For list archives: http://lists.mysql.com/mysql To unsubscribe: http://lists.mysql.com/[EMAIL PROTECTED]
