Count number of checkboxes

[stanswx]

I have a custom field called Clients that is a checkbox field. I use it to show which of our clients are reporting a bug or feature request. What I want to be able to do is create a column that counts how many clients are checked off for each bug. Then I would be able to sort the list to show the highest # of clients that the bug/feature is affecting. I'm familiar with the count command in PHP, but not sure how to tie it to my custom_Clients custom field. Any ideas? Running v1.2.4. Thanks!

[atrol]

First you have to look at table mantis_custom_field_table for the id of your custom field.
You get the values by searching for this id in table mantis_custom_field_string_table column field_id

[fotoforward]

I'm curious in how to implement this with the relation variable.

On the view_all_bugs page i want to add a column with the number of relations of an issue per row.
Any thoughts?