In Microsoft SQL Server, for example, a primary key usually equates to a clustered index. In SQLite, a primary key is usually just a unique index and is distinct from the special rowid column name.

Under far too many circumstances, those responsible for modeling data are ignoring the above perspective on primary keys and are simply defining surrogate keys for everything in their data model. One ...

When working on a multidimensional design, every fact table within scope should be handled with care. In an ideal world, each low-level fact table represents the metrics related to a business event.

Duplicate and Ignore on MySQL Inserts. MySQL table primary keys and unique indexes prevent multiple rows with the same index from being added to the table. If you try to insert a duplicate row ...