Sparse Column With NULLs

  • In a table containing a sparse column (mainly) NULLS, is there any way with TSQL under SQL2000 to propagate a clomun value down the column replacing the NULLS until encountering another "NOT NULL" value?

  • Would the non null rows have a relationship to the null rows other than physical order? Conceptually I think a cursor is easiest to envision, sort the data however makes sense, then keep track of the last non null value and update as you go. Set based is better when you can manage, not sure how to approach it in this case. Perhaps other readers will!

    Andy

  • Since SQL Server doesn't track physical order, you need someway to order the rows. As Ansy said, you can use a cursor, but you still need ordering.

    Steve Jones

    steve@dkranch.net

  • Thanks, folks, for the suggestions. I finally resorted to the cursor method. Takes about 10 minutes to do 300k rows.

    I'm sure the problem could be solved in

    a better way but this works OK for now.

    Thanks, Bill Washburn

  • If you could post your cursor we can look at offer suggestions since this will give us an idea of what exactly you are doing.

    "Don't roll your eyes at me. I will tape them in place." (Teacher on Boston Public)

  • 10 mins aint bad! Will you end up reprocessing all 300k rows every day?

    Andy

  • Thanks folks,

    Turns out to be 10min to load 350k into first

    table, select out and load 5 tables and then

    do the cursor fixup on the FK table.

    It will run each night. I will post also but

    am busy today with crazy time here at work.

    Bill Washburn

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