Order products by a custom field

[patben]

Hi

I want to order the products in one category by a custom field is that posible??

For example i want to order books whith a custom field that is the year of the book release

[balai]

You need a filtering extension.
Look here: http://breakdesigns.net/extensions/custom-filters

[patben]

with custom filters can I sort products with a custom field?

[balai]

oh sorry i thought you wanted to filter products by custom field.

To sort them by custom field i think that you should change the sql query in the category pages.
You can find it at the file: administrator\components\com_virtuemart\models\product.php

The function is the sortSearchListQuery

[patben]

I would be obliged if you give me a little more information, because I could not understand how to do what im ask.

Thank you

[patben]

any idea ?

[balai]

It needs some sql knowledge.
You should join the query with the product_customfields table of the database and then change the order by to 1 of the fields of this table

[patben]

I have to make changes in this file only, administrator\components\com_virtuemart\models\product.php ?

[balai]

If you want to have your products to be sorted only by a custom field yes this file is enough.
If you want to have other sorting options too, you should add the sort by custom field option also to the drop-down list that regrads the sorting

[patben]

i want i can choose sort by custom field in sort by page of settings of virtuemart but don't lost the other options of sort by. it is posible?