Validation rule: uniquePair

I wonder if there is CActiveRecord validation rule with which i can check for two unique column values.

I understand i can quickly add rule for one column

array('username', 'unique'),

or more columns (which will validate separatly

array('username,email', 'unique'),

But how should i chec for unique pair (two columns)

In database column i have index

..

PRIMARY KEY (`someColumn1`,`someColumn2`)

..

should i write my own validation rule?

nobody?

Could be that nobody is answering as this topic has already been on the forum… you just need to search…

Here is one similar that I found - http://www.yiiframew…p?/topic/15622-

thanks, i just wanted to know is there already built-in validation for this