primary keys

[renny]

Hello,

Currently I have a table with an auto_increment column as the primary key but lately there are so many ppl tap into the table, we've been having problems with it.

I have a clientID and reportDate columns and those combined are supposed to be unique, ie. the same clientID and reportDate (combined) are not supposed to appear in more than one record. But lately people have been changing it around and it causes an error because somehow someone mistakenly change two records so we have three different records with the same clientID and reportDate (combined).

I want to prevent this to happen in the future and would like to make these two columns to be a primary key. How do I do this? I keep trying to alter the table but it keeps giving me the multiple primary keys defined error.

Please help... thanks so much in advance!

-Ren

[superwormy]

I don't believe you can have two primary keys...

You could have a UNIQUE field with an INDEX... does that help?

[Sxooter]

A multi-key unique index is most likely the answer here.

Note that a Primary key is just a name for the field(s) you'll be using mostly to reference a table. It's basically just a unique index with an attitude. 🙂