# Incremental file

**URL:** <https://forum.cloverdx.com/t/incremental-file/910>\
**Category:** CloverDX Platform\
**Created:** [August 9, 2011, 12:00am UTC](https://forum.cloverdx.com/t/incremental-file/910 "2011-08-09T00:00:00Z")\
**Posts on this page:** 2\
**Page:** 1

<div class="post-metadata">

**Author:** ![kasturi](https://avatars.discourse-cdn.com/v4/letter/k/a698b9/32.png) [@kasturi](https://forum.cloverdx.com/u/kasturi)\
**Post date:** [August 9, 2011, 12:00am UTC](https://forum.cloverdx.com/t/incremental-file/910/1 "2011-08-09T00:00:00Z")

</div>

Hello Agata,  
Incremental key is working fine for most of my graphs with the exception of one scenario.  
I am getting this error  
Mixing of GROUP columns (MIN(),MAX(),COUNT(),…) with no GROUP columns is illegal if there is no GROUP BY clause

when I try to use the incremental key in this sql

SELECT lower(trim(a.email)) as email,MIN(o.order\_date) AS order\_date,max(address\_id) FROM  
address a,  
order\_header o,  
payment p  
where  
a.address\_id\>#key01 and  
lower(trim(a.email)) is not null and  
p.billing\_address\_id=a.address\_id AND  
p.payment\_id=o.payment\_id  
group by lower(trim(a.email))

Thanks and best regards,  
Kasturi

---

<div class="post-metadata">

**Author:** ![ikulman](https://avatars.discourse-cdn.com/v4/letter/i/ebca7d/32.png) [@ikulman](https://forum.cloverdx.com/u/ikulman)\
**Post date:** [August 11, 2011, 7:18am UTC](https://forum.cloverdx.com/t/incremental-file/910/2 "2011-08-11T07:18:10Z")

</div>

Hello, the error message you stated is a database error message so I think your problem is in your sql query / database. Try running your query with a sample #key1 value in your database to see if you get the same error message.