Re: Index question

Dirk Moolman said: > We have a new query, with a where-clause: > > where a < b (a & b are date fields) > and c = 0 (c can have values from 0 to 270) > and d = "2" (d can have 4 different values) > > > What is the best way to write this where clause, and which are the best > indexes to use ? > > The table has a total of 32 million records. > > > > > My own thoughts were: > > where d = "2" (get rid of most of the records) How do you know this gets rid of most of the records? Is 2 a very rare value? > and c = 0 (reduce the above subset to about 25%) > and a < b (leave the sequential scan for this remaining data > set) > > > And create indexes on c & d (which brings up another question - > composite or stand alone ?) Are all these columns in the same table? Why don't you want to index a or b? -- Bye now, Obnoxio "C'est pas parce qu'on n'a rien ' dire qu'il faut fermer sa gueule" - Coluche A smile is a gift that is free to the giver and precious to the recipient. But giving someone the finger is free too, and I find it more personal and sincere. sending to informix-list