SCD means If the data in the dimension is happen to change very rarely,
Mainly SCD 3 types
1)SCD-1:HERE THE PREVIOUS DATA OVERWRITE BY CURRENT DATA
MEANS HERE ONLY MAINTAIN CURRENT DATA.
2)SCD-2: HERE JUST ADD THE ADDITIONAL RECORDS
IN SCD2 3 TYPES1)VERSIONING2)FLAGVALUE3)EFFECT DATE RANGE
VERSIONING: MEANS HERE JUST SEND THE UPDATED RECORDS TO THE TARGET ALONG WITH VERSION NUMBER.
NEW RECORDS WILL BE SENDING TO THE TARGET ALONG WITH PRIMARY KEY
FLAGVALUE:HERE UPDATED RECORDS SEND TO THE TARGET ALONG WITH 0
AND RECENT RECORDS SEND TO THE TARGET ALONG WITH 1
EFFECTIVE DATE RANGE:MEANS HERE TRACKS THE BOTH PREVIOUS AND CURRENT DATA
3)SCD-3: HERE MAINTAINS JUST PREVIOUS AND CURRENT DATA.