Which concept describes querying data from two or more tables usually linked by a key field and a foreign key?

Which concept describes querying data from two or more tables usually linked by a key field and a foreign key?

• A. Fields Requested
• B. Computed Fields
• C. Group By
• D. Joining Tables

Answer: (D)

Joining tables is the concept described when you query data from more than one table that are linked by a key field and a foreign key. In a relational database, a primary key uniquely identifies a row in its table, and a foreign key in another table points to that key to establish a relationship. A join brings together rows from the related tables where the key values match, producing a single result set that contains fields from both tables. For example, linking a customers table to an orders table on the customer_id field lets you fetch each customer’s name alongside their orders. This is typically written with a join clause in SQL, such as selecting from customers joined to orders on the matching key. The other options don’t describe this cross-table linkage. Selecting fields refers to pulling data from one table, computed fields are derived values, and Group By aggregates data within a single result set rather than combining rows from multiple tables.

Joining tables is the concept described when you query data from more than one table that are linked by a key field and a foreign key. In a relational database, a primary key uniquely identifies a row in its table, and a foreign key in another table points to that key to establish a relationship. A join brings together rows from the related tables where the key values match, producing a single result set that contains fields from both tables. For example, linking a customers table to an orders table on the customer_id field lets you fetch each customer’s name alongside their orders. This is typically written with a join clause in SQL, such as selecting from customers joined to orders on the matching key.

The other options don’t describe this cross-table linkage. Selecting fields refers to pulling data from one table, computed fields are derived values, and Group By aggregates data within a single result set rather than combining rows from multiple tables.