On 20 Jul 2011, at 4:21pm, KeithB wrote: > I'd like to create a temporary table to "shadow" one of my persistent > tables. It will have the same columns and hold "override" values that, > when present, take precedence over the real values. So, I'd like to > search for a row by primary key, looking first in the override table, > and if not found, then in the real table. The result will always be > zero or 1 rows. > > I can do this with two SELECTs, but that doesn't seem to be the most > efficient approach. I'm sure this is easy and obvious with some > combination of UNION, ORDER BY, and LIMIT or something, but I can't > figure it out.
Had you considered a VIEW ? A VIEW is a way of saving a SELECT statement that can be accessed as if it's a TABLE. You could use a SELECT that uses a JOIN to pick a value from the appropriate TABLE. Simon. _______________________________________________ sqlite-users mailing list [email protected] http://sqlite.org:8080/cgi-bin/mailman/listinfo/sqlite-users
