For more information:
- For more information on SQL Server, visit https://docs.microsoft.com/en-us/sql/t-sql/lesson-1-creating-database-objects?view=sql-server-ver15.
- For more information on Oracle, visit ;https://docs.oracle.com/en/database/oracle/oracle-database/18/cncpt/tables-and-table-clusters.html#GUID-F845B1A7-71E3-4312-B66D-BC16C198ECE5.
- For more information on PostgreSQL, visit https://www.postgresql.org/docs/11/ddl-basics.htm.
- For more information on filtered indexes, visit https://docs.microsoft.com/en-us/sql/relational-databases/indexes/create-filtered-indexes?view=sql-server-ver15. In PostgreSQL, this is called a partial index. For more information on this, visit https://www.postgresql.org/docs/11/indexes-partial.html.
