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Hi all,
I have a couple of largish tables that need to be indexed on columns with very low cardinality. Sounds like a job for Bitmap Indexes.
Ok, then. I've scoured Dejanews and read everything there that I can find, I've spent several hours following links from Altavista and I've trawled my way through the manuals. Could someone please help clarify a few points.
I get the good old 00901 error when I try and create my indexes. Now I've seen lots of replies to posts on that message and lots of FAQs. So far I've only managed to get more confused as I go. I am running 7.3.3 on an NT4 box with a single CPU.
One thing in common with everything I've read is that <compatible = 7.3.2.0.0> (or better) must be set. As I am running 7.3.3 should that be in there?
After that it all goes to pot. Some posts say that the parallel query option must be set, others say it isn't necessary. Which is correct?
Another problem is how to set it if it is necessary. So far I've seen:
event = "10111 trace name context forever" event = "10112 trace name context forever" event = "10224 trace name context forever"
as being the advised way to do it and I've seen:
PARALLEL_MIN_SERVERS
PARALLEL_MAX_SERVERS etc.
as being correct. Which is right? If it's the second way then do I enter '1' for both values. I realise that it's processes not actual processors for parallel queries (or so several of the posts said) but it all seems a bit grey.
Apologies if I seem a bit thick but things appear to be a little vague. Any assistance will be much appreciated.
TIA --
This post is made entirely from recycled ones and noughts