I have one record where I want to update a field with the data from an identical field in another table. Problem is that the lookup table contains duplicate records so I just want to bring data from the first matched record.

Here's what I have right now but I get this error: 

> 
> too many values
> 
> 
> 

My query is:

```
UPDATE T_TABLE1 T1 
SET T1.UPDATEFIELD =  (SELECT DISTINCT(T2.itemtag), MAX(T2.UPDATEFIELD) 
                       FROM T_TABLE2 T2  
                       WHERE T2.ITEMTAG = T1.ITEMTAG 
                       GROUP BY T2.itemtag)

```