# JuliaDB groupby many columns

**URL:** <https://discourse.julialang.org/t/juliadb-groupby-many-columns/58935>\
**Category:** General Usage\
**Tags:** juliadb\
**Created:** [April 9, 2021, 5:10pm UTC](https://discourse.julialang.org/t/juliadb-groupby-many-columns/58935 "2021-04-09T17:10:20Z")\
**Posts on this page:** 1\
**Page:** 1

<div class="post-metadata">

**Author:** ![Fabien1](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/fabien1/32/23818_2.png) [@Fabien1](https://discourse.julialang.org/u/Fabien1)\
**Post date:** [April 9, 2021, 5:10pm UTC](https://discourse.julialang.org/t/juliadb-groupby-many-columns/58935/1 "2021-04-09T17:10:20Z")

</div>

Hi guys ,

I’m trying to groupby using JuliaDB , everything works well except when i want to apply a function that takes two columns in one time.

```julia
 JuliaDB.groupby(
    (
        TOTAL_PAID = :PRICE => sum, 
        FREQUENCY_IN_DAYS = :ORDER_DATE => handle_dates,
        RECENCY_IN_DAYS = :ORDER_DATE => (x -> Dates.value(Date(now()) - maximum(x))),
        COUNT_ORDERS_LAST_MONTH = :ORDER_DATE => countOnlyLastMonth,
        TOTAL_PAID_LAST_MONTH = [:ORDER_DATE, :PRICE] => countOnlyLastMonth,
        COUNT_ORDERS = length
    ),
    t, :USER_KEY)

```

It’s this line that doesn’t work  
`TOTAL_PAID_LAST_MONTH = [:ORDER_DATE, :PRICE] => countOnlyLastMonth,`  
With DataFrames.groupby you would do it as following :  
`[:ORDER_DATE, :PRICE] => countOnlyLastMonth => :TOTAL_PAID_LAST_MONTH,`

How can i do that with juliaDB ? Thank you