What does an INNER JOIN do when combining two tables?

• A. Returns all records, regardless of matches
• B. Returns only duplicate records
• C. Returns records with matching data from both tables
• D. Returns all records from the left table

Answer: (C)

An INNER JOIN is a type of join used in SQL to combine rows from two or more tables based on a related column between them. When performing an INNER JOIN, the resulting dataset includes only those records where there is a match in both tables. This means that both tables must have entries that meet the specified join condition for those records to be included in the output.

For instance, if you have two tables, one listing customers and another listing orders, and you want to find all customers who have placed orders, an INNER JOIN would only return the customers who have matching entries in the orders table. This is particularly useful in practical scenarios where you need to extract relevant data that is related across multiple tables in a meaningful way, ensuring that only the intersecting values are considered in the result set.