Outer join is used in scenarios where you want what?

Outer join is used in scenarios where you want what?

• A. Used when you want all records from one table even if there is no matching record in the joining table
• B. Nested queries require matching relations
• C. Only join matching records
• D. Only used for single-table queries

Answer: (A)

Outer join is used when you want to preserve all records from one table while bringing in related data from another table whenever it exists. This lets you see every row from the primary table (for example, all customers) even if there isn’t a matching row in the joined table (no orders), in which case the related fields come back as NULL. If you only wanted rows where there is a match, you’d use a different join type that excludes non-matching rows. The other options don’t fit because they describe different scenarios (focusing on only matching data, or on single-table queries, or on nested queries).

Outer join is used when you want to preserve all records from one table while bringing in related data from another table whenever it exists. This lets you see every row from the primary table (for example, all customers) even if there isn’t a matching row in the joined table (no orders), in which case the related fields come back as NULL. If you only wanted rows where there is a match, you’d use a different join type that excludes non-matching rows. The other options don’t fit because they describe different scenarios (focusing on only matching data, or on single-table queries, or on nested queries).