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  • Jaime Montoya thinks this is interesting:

Even though we identified several foreign key relationships among our tables, we are not going to create foreign key constraints in our data mart. Foreign key constraints put a strain on the database engine during a large data load. Large data loads are quite common in the data mart environment.

Note

For the data mart that I created for an OLAP cube, my database design included several foreign key relationships for table connections and levels of hierarchies in the dimension tables. However, I did not create foreign key constraints to avoid putting a strain on the database engine in case the ETL process requires large data loads.