4.2.1 Type 1 MethodologyType 1 Methodology

The Type 1 methodology overwrites old data with new data and therefore does not track historical data. This is useful for making changes to dimension data.

Example:

The application installer populates one row per dimension for the seeded dimensions in this table.

Table 4-1 Type 1 Methodology

N_PRODUCT_SKEY	V_PRODUCT_NAME	D_START_DATE	D_END_DATE	F_LATEST_RECORD_INDICATOR
1	PL	5/31/2010	12/31/9999	Y

In this example,

• N_PRODUCT_SKEY is the surrogate key column which is a unique key for each record in the dimension table.
• V_PRODUCT_NAME is the product name.
• D_START_DATE indicates the date from which this product record is valid.
• D_END_DATE indicates the date to which this product record is valid.
• F_LATEST_RECORD_INDICATOR with value 'Y', which indicates this is the latest record in the dimension table for this product and 'N' indicates it is not.

If the V_PRODUCT_NAME column is set as a Type 1 SCD column and if there is a change in the product name to 'Personal Loan' from 'PL' in the above example, in the next processing period, then when SCD is executed for the new processing period the record in the above example changes to:

Table 4-2 Type 1 Methodology

N_PRODUCT_SKEY	V_PRODUCT_NAME	D_START_DATE	D_END_DATE	F_LATEST_RECORD_INDICATOR
1	Personal Loan	6/30/2010	12/31/9999	Y