On Wed, Dec 10, 2003 at 04:54:54PM -0500, Tom Lane wrote: > Currently, this is accomplished by the roundabout method of converting > the WHERE clause to CNF (AND-of-ORs) and then simplifying duplicate > sub-clauses within an OR: > (a AND b) OR (a AND c) > expands by repeated application of the distributive law to > (a OR a) AND (a OR c) AND (b OR a) AND (b OR c)
This is wrong. What would be true however is: (a OR b) AND (b OR C) = (a AND b) OR (a AND c) OR (b AND b) OR (b AND C) (Replace AND by * and OR by +) Kurt ---------------------------(end of broadcast)--------------------------- TIP 4: Don't 'kill -9' the postmaster