CVSROOT:        /cvsroot
Module name:    pgsql-server
Changes by:     [EMAIL PROTECTED]       04/04/19 22:00:27

Modified files:
        doc/src/sgml/ref: create_index.sgml 

Log message:
        > >> My question is whether postgres can index null values, and if not, do I
        > >> have to accept a full table scan when locating records.
        > >
        > > It indexes them, but "is null" is not an indexable operator, so you
        > > can't directly solve the above with a 3-column index.  What you can do
        > > instead is use a partial index, for instance
        > >
        > > create index i on CUSTOMER.WCCustOrderStatusLog (WCOrderStatusID)
        > > where Acknowledged is null and Processing is null;
        >
        > That's a very nifty trick and exactly the sort of answer I was after!
        
        Add CREATE INDEX doc mention of using partial indexes for IS NULL
        indexing;  idea from Tom.


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