Query on Custom Fields Table

[miriamxdeig]

Hi,

I need to make a query to retrieve custom fields for a given user.

So I pass the user Id and I would like to return all fields in column.
This is difficult to me, with a good performing query.

And I think it is due to the way the custom fields table is made:
item_id, field_id, value.
Then I made a query to obtain a pivot table ( rows to columns ):

SELECT
U.id, U.username, U.name,FV.value
MAX(CASE WHEN FV.field_id = 8 THEN FV.value END) AS company,
MAX(CASE WHEN FV.field_id = 29 THEN FV.value END) AS area_manager,
MAX(CASE WHEN FV.field_id = 33 THEN FV.value END) AS company_type
FROM kizgv_users U LEFT JOIN kizgv_fields_values FV ON U.id = FV.item_id

Still that's not at all performing and I got a 500 error if I do it in a medium site .

Can you suggest a smarter way?