filter duplicate records

[von Horst]

how can I create a filter view of a list that shows only records containing duplicate data within a specified field?

using this pre-filter query:
SELECT IP, COUNT(IP) FROM joomla6 GROUP BY IP HAVING COUNT(IP) > 1

what am I missing?

 

[rob]

The prefilter query won't work in the way you are trying to use it.
The only way I can think of achieving this would be to create a mySQL view and link a fabrik list to that.