EX:- Suppose we have an customer Table, we have some fields which are frequently, ofliny, slowly, Rarely, Rapidly changed
Different types of loadings
- Initial
- incremental
- Initial data (source) :-
C ID CN Add
11 A HYD stored in Achieve Data base or OLTP or Source
22 B SEC
33 C DEL
The information is should from 2000 to 29th dec 2010
This data is stored in Target 
Ware House Before Data
- Source (After data) :-
CID CN Add value column
11 A HYD Copy
22 B GNT Edit
33 E VZD insert
- Refresh the target data with source data based on type 1, type 2, type 3
- Differences :-
Compare Before Data with After Data
Extract Extract
Target Source
Data Data
- If there are any changes in key columnInsert
- If there are any changes in value columnedit
Output :-
Table 1 :-
EX: Before Data(Target)
CID CN Add
11 A HYD
22 B GNT
33 C DEL
32 D VZD
After Data: (Source)
CID CN Add
11 A ASM Edit
22 B GNT copy
44 G PUNE insert
32 E Cal edit
- Type 1 will not maintain historical data, maintains only current data .
Output :-
CID CN Add
11 A ASM
22 B GNT
33 C DEL
44 G PUNE
32 E CAL
- Before Data will not Maintain history
Type 1 implementation will always happen in ODS
Dimensional Tables CUST id, C NAME, C ADD , Gender
Fact Tables C id, BAL, AREA, Trane Type , Data Maintained History
Type 2 :- (Maintain History)
After Data :- (Source) Before Data :- (Target)
CID CN ADD CID CN ADD
11 A HYD 11 A HYD
22 B GNT 22 B SEC
44 E PUN 33 C DEL
Output :-
CID CN ADD
11 A HYD
22 B GNT
33 C DEL
———————————–
22 B GNT
44 E PUN