I'm having trouble formulating a query. This is a simplified version of the tables:
ombcase
------------
case_pkey integer, primary key
casename varchar
insdatetime timestamp w/o time zone
status_fkey integer, foreign key
status
--------
status_pkey integer, primary key
statusid varchar
statuschange
--------
statuschange_pkey integer, primary key
insdatetime timestamp w/o time zone
ombcase_fkey integer, foreign key
oldstatus_fkey integer, foreign key
newstatus_fkey integer, foreign key
active integer, not nullable
The idea should be obvious, but to explain, insdatetime is set when a new record is created in any table. All records in ombcase have a foreign key to status that can't be null. When status changes, a record is created in statuschange recording the old and new status keys, and the time (etc).
The goal is to find records in ombcase that have not had a status change in xx days. If the status has not changed, there will be no statuschange record.