In SQL we support non-standard clause called ON CONFLICT / OR. It is not a separate clause which can appear in INSERT/UPDATE statements or as a column option in CREATE TABLE statements. See examples ...

See Updating PROC SQL and SAS/ACCESS Views ... To add, drop, or modify a column's definition or attributes, use the ALTER TABLE statement, described in ALTER TABLE Statement. In the SET clause, a ...

For example, to retrieve all columns from a table named "employees," the query would be: ```sql ... statement. Having an index will allow you to return your specific data as indicated in the where ...