Sounds like the "index death spiral" to me. My simple sanity check: when the total number of columns indexed is greater than the number of columns in the table, there is likely a design or tuning problem. Often times, even before then... On Thu, Aug 11, 2011 at 1:45 PM, Ram Raman <veeeraman@xxxxxxxxx> wrote: > Listers, > > I am looking at a table in our system and it has 12 indexes, we are > planning on adding another one. I am aware of the effects of having too many > indexes, but in this case adding an extra index helps a certain query that > runs slow. Other queries and most other operations against the table > are acceptable too. I see a few tables like this; is there a number above > which is considered a no-no when it comes to adding more indexes. > > PS. The tables and queries are structured in a way that seem to require > several indexes - it is a third party product. > > TIA, > Ram. > -- Regards, Greg Rahn http://structureddata.org