Post reply

Index on a Bit Column

  • July 1, 2005 at 1:27 am

    #109795

    Hi Guys,

    I have a question.

    Our developers have recently made changes to our database (Only in test you'll be glad to hear).

    We have calculations that run each night and they usually take about 4.5 hours..that's fine. There is a function that is used in many of the procedures and this is now using 2 new columns which have been added to an existing table. These are both Bit fields.

    We have been discussing indexing these bit columns. I have suggested adding them into the composite index of the source table, but our developers are also suggesting they are indexed separately.

    The reason for this is that the calcs now take 10 hrs.....eeeekkk.

    Does anyone have experience of this? Are there any merits to indexing bit fields separately ?

    Your comments would be gratefully received.

    Thanks Guys..and Gals

    Regards..Graeme

  • July 1, 2005 at 3:00 am

    #570260

    Since there are only two possible values to index I do not think the indexes would do you much good. Unless there is a very small amount of the values that have one of the two values.

    --
    Chris Hedgate http://www.hedgate.net/
    Contributor to the Best of SQL Server Central volumes
    Articles: http://www.sqlservercentral.com/columnists/chedgate/

  • July 1, 2005 at 3:25 am

    #570263

    That was also my understanding !!

    Thanks for that

Viewing 3 posts - 1 through 2 (of 2 total)

You must be logged in to reply to this topic. Login to reply