# Create sort\_ function for functional field
**URL:** https://discuss.tryton.org/t/create-sort-function-for-functional-field/1073
**Category:** Developer
**Created:** [January 24, 2019, 5:44pm UTC](https://discuss.tryton.org/t/create-sort-function-for-functional-field/1073 "2019-01-24T17:44:06Z")
**Posts on this page:** 3
**Page:** 1
### Author:  [@iehoshia](https://discuss.tryton.org/u/iehoshia)
#### Post date: [January 24, 2019, 5:44pm UTC](https://discuss.tryton.org/t/create-sort-function-for-functional-field/1073/1 "2019-01-24T17:44:06Z")
Hi,
I was reading the docs about functions to order funtional fields [6], [7] and reviewing some examples on tryton git [0], [1], [2], [3], [4], [5] but I could not find and example on how to use for a specific case that have.
Basically I have a model to record the gathering moves of every month and a group. Every group have more than 5 people, it will vary:
Moves:
Group, Month, Date,
Moves Lines:
Move, Party, Amount
I added a custom field that calculate on Party that get the sum of the move lines and it works fine, but I wish to order from highest to lowest.
Where could I find an example of how can order these type of field?
Thanks in advance!
[0] [party/party.py at develop · tryton/party · GitHub](https://github.com/tryton/party/blob/develop/party.py#L100)
[1] [account/move.py at f8e616ba2aa40502e2f478c8506805adeee0f424 · tryton/account · GitHub](https://github.com/tryton/account/blob/f8e616ba2aa40502e2f478c8506805adeee0f424/move.py#L143)
[2] [product/product.py at develop · tryton/product · GitHub](https://github.com/tryton/product/blob/develop/product.py#L279)
[3] [purchase\_request\_quotation/purchase.py at 5d151e6896a0a1374f3b4f428425aab0515024de · tryton/purchase\_request\_quotation · GitHub](https://github.com/tryton/purchase_request_quotation/blob/5d151e6896a0a1374f3b4f428425aab0515024de/purchase.py#L320)
[4] [timesheet/line.py at develop · tryton/timesheet · GitHub](https://github.com/tryton/timesheet/blob/develop/line.py#L354)
[5] [party/address.py at b184b5996b7e983e0ce4beb75216962c532ef3b4 · tryton/party · GitHub](https://github.com/tryton/party/blob/b184b5996b7e983e0ce4beb75216962c532ef3b4/address.py#L255)
[6] [http://docs.tryton.org/projects/server/en/latest/ref/models/fields.html?highlight=ordering#ordering](http://docs.tryton.org/projects/server/en/latest/ref/models/fields.html?highlight=ordering#ordering)
[7] [http://docs.tryton.org/projects/server/en/latest/ref/models/fields.html?highlight=ordering#trytond.model.fields.Field.convert\_domain](http://docs.tryton.org/projects/server/en/latest/ref/models/fields.html?highlight=ordering#trytond.model.fields.Field.convert_domain)
---
### Author:  [@ced](https://discuss.tryton.org/u/ced)
#### Post date: [January 25, 2019, 2:24pm UTC](https://discuss.tryton.org/t/create-sort-function-for-functional-field/1073/2 "2019-01-25T14:24:56Z")
> [@iehoshia](#):
>
> Where could I find an example of how can order these tye of field?
There is no such example because it would be resource consuming.
Any way, you have to make a join (adding to `tables` argument) with a query the will return the party id and the `SUM`. Then you return the clause to order with the `SUM` column of your query.
---
### Author:  [@JCavallo](https://discuss.tryton.org/u/JCavallo)
#### Post date: [February 15, 2019, 11:20am UTC](https://discuss.tryton.org/t/create-sort-function-for-functional-field/1073/3 "2019-02-15T11:20:53Z")
I just updated the training module with an example of an “order” method implementation:
> **[5.0 step10](https://github.com/coopengo/tryton-training/wiki/5.0-step10)**
>
> Contribute to coopengo/tryton-training development by creating an account on GitHub.
Search for “Defining a order method”
Edit : For your use case, you would have to add an entry in the “tables” dict which is a full sub-query.