I'm reading "Master oracle SQL" 2nd edition, p. 608. by Mishra
on p.608 it mentions that the regexp_like condition in the where clause has the same problem as any function in the where clause as it precludes use of indexes.
is this true? It seems a bit interesting, although makes sense in which functions that change the value of a column wouldn't invoke an index - however is this true for any function that doesn't change the 'hard coding' so to speak. For example an UPPER function in the where clause could invoke the index to look for all upper case values.
I'm asking because the book is a bit old (10g) and things may have changed since then (for example from the 6-7 textbooks I've read on oracle SQL I don't remember reading about this), and also I've found a few articles that hover over this topic but don't necessarily point to the answer i'm looking for.
Thanks much.
Also I'm going to go take a short nap, but I wanted to ask this question before I forgot (I got a few on my list), so I can respond a bit later.
Thanks again~