What is a subquery in SQL, and how is it different from a JOIN operation?
- A subquery is a query nested within another query, and it can be used to return a single value, a single row, multiple rows, or a table. Unlike a JOIN operation, which combines columns from multiple tables based on a related column between them, a subquery is used to filter or manipulate data within the same table or from different tables based on a condition specified in the main query.
- A subquery is a query that combines columns from multiple tables based on a related column between them. Unlike a JOIN operation, which is used to filter or manipulate data within the same table or from different tables based on a condition specified in the main query, a subquery is nested within another query and can return a single value, a single row, multiple rows, or a table.
- A subquery is a query that returns all records from both tables, regardless of any related columns between them. Unlike a JOIN operation, which combines columns from multiple tables based on a related column between them, a subquery is nested within another query and can be used to filter or manipulate data within the same table or from different tables based on a condition specified in the main query.
- A subquery is a query that returns only matching records from both tables. Unlike a JOIN operation, which combines columns from multiple tables based on a related column between them, a subquery is nested within another query and can be used to filter or manipulate data within the same table or from different tables based on a condition specified in the main query.
A subquery in SQL is a query nested within another query, allowing for more complex and dynamic data retrieval and manipulation. It can be used to filter, sort, or aggregate data based on specific conditions or criteria defined in the outer query. Unlike a JOIN operation, which primarily focuses on combining columns from multiple tables based on related columns, a subquery operates within the context of a single query and can perform various operations such as selecting, filtering, and aggregating data based on specific requirements.
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