SCD TYPE1 MAPPING

The SCD Type 1 methodology overwrites old data with new data, and therefore does no need to track historical data .

1. Here is the source
   

1. We will compare the historical data based on key column CUSTOMER_ID.
2. This is the entire mapping

1. Connect lookup to source. In Lookup fetch the data from target table and send only CUSTOMER_ID port from source to lookup
   
2. 
3. Give the lookup condition like this
   
4. 
5. Then rest of the columns from source send to one router transformation
   
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7. In router create two groups and give condition like this
   
8. 
9. For new records we have to generate new customer_id. For that  take a sequence generator and connect the next column to expression .New_rec group from router connect to target1(Bring two instances of target to mapping, one for new rec and other for old rec) .Then connect next_val from expression to customer_id column of target
   
10. 
11. Change_rec group of router bring to one update strategy. and give the condition like this
    
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13. 

Instead of 1 you can give dd_update in update-stratgy. Then connect to target