Re: Enough of the "DB2" thread, let's talk about Fragmented Tables

Colin Dawson wrote: > With the use of SANs for storing the database how effective will the use of > fragmented tables be? I've got a few very large tables (16+ chunks) and was > considering splitting it into 6-8 fragments, they all have serial columns > and one has 7 indexes (or is it indeces). The last time I did anything real > with them was splitting a table across 4 disks, it improved the performance > no end. I'm not convinced I will get an improvement when using a SAN If your fragmentation scheme is set up for it and your queries can take advantage of them then enabling parallel queries of multiple fragments and fragment elimination can improve performance even above what you are gaining from an intelligent SAN. If not, then the only advantage of fragmentation for you will be the possibility of maintenance simplification for rolling data. Art S. Kagel