Here's the scenario:
9 different tables, 'ca1' through 'ca9', each with unique index named 'ca_id' which relates them.
Each of the 9 has a field 'ca_last_update' reflecting the date the last change to that record was made.
View which contains one record per ca_id and the oldest value of ca_last_update from among its 9 records. If any of the 9 dates for a given ID are NULL, need NULL.
Tried creating view with sub-queries but, of course, MySQL doesn't allow that. No go.
Ended up creating 9 separate views (one for each table), another view that uses UNIONs to combine them into one large record set (resulting in 9 x the number of unique IDs - a really big number), and still another to get the MIN() of the date column for each ID from that view.
I feel like I'm making this too complicated. There's got to be a better, faster way... Anybody know what that is?