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.