Re: [PERFORM] Deceiding which index to use

[Mezei Zoltán]

Richard Huxton wrote: > Mezei Zoltán wrote: > Q1. Why are you storing a numeric in a varchar? Because it's not always numeric info. :/ > Q2. How many unique values does anumber have? And how many rows in > subscriber? About 10k distinct anumbers and 20k rows. Nothing special... > Q3. What happens if you create the index on plain (anumber) and then > test against '555555555'? Nothing, everything is the same - the problem lies on the other table's index usage, using this index is fine. Zizi