SCD determining records as changed when they are not changing

• jere42

  Old Hand

  Points: 305

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  February 16, 2011 at 1:05 pm

  #235145

  I have a dataflow containing an SCD that was working perfectly. I was charged with adding 3 columns (in addition to the original columns) to the feed. The working SCD had one historical attribute (ApplicationName), was type2 with RowStartDate, RowEndDate, and IsRowCurrent (Y|N).

  STEP1) adding the columns to the table feeding the SCD. Columns added will also be historical attributes(AgentGroup,SL_Time, and SL_Percentage). Adjusted the primer of this table to load the 3 additional columns and it works so the new version of the feed table is all set.

  STEP2) Inside the SCD (yes we used the wizard, don't start on that, not alot of recs) added the 3 new cols as historical attributes for a total of 4 historical atts columns, plus the original 2 business key columns.

  It is working fine except that the dim table we are bumping this feeder table against starts the run with 4885 records and ends up with 8144 records. Upon inspection, I am finding many records that have been expired with a new current record added but, there was no change apparent on any of the 4 historical attribute columns between the records!

  I can't figure out why it would think the records are different and process a change. There are I think 30 cols total in the dim table tbldApplicationNew and tblApplicationNew (feeder file) has 6 cols (2 buskeys, 4 attributes)

  I am having trouble figuring out why this behaves this way and also, how would you debug this? I am going to remove the 3 additional hist. atts. out of the SCD task and see if it goes back to where it was. I got a feeling this is so simple it's stupid but, I don't get it (yet...)