One cannot have everything the way he would like it --Mark
Twain
In the absence of other advanced techniques for star join
optimization, nested fact join with dimensions while ensuring
that the indexes are used for each dimension join delivers
reasonable performance.
The following indexes are created on the star schema example shown:
- Primary key unique index on surrogate key for each dimension. One index each is created on: calendar (calendar_key), transaction_details (transaction_detail_key), product (product_key), sales_organization (sales_org_key)
- One index is created for each foreign key on the fact table: sales_transaction (calendar_key), sales_transaction (transaction_detail_key), sales_transaction (product_key), sales_organization (sales_org_key)
- In addition some indexes may be …