The INNER JOIN clause…
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returns all the matching rows from 2 tables.
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returns only the rows from the first table, which have non-matching values with the second table in the field on which the 2 tables are joined.
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returns all rows from 2 tables.
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returns all rows that have matching value in the field on which the 2 tables are joined.
INNER JOIN returns only rows where both tables have matching values in the joined field(s). Non-matching rows from either table are excluded from results. Option A is incorrect because INNER JOIN doesn't return 'all matching rows' - it returns rows with matches in BOTH tables. Option B describes LEFT JOIN. Option C describes FULL OUTER JOIN. Option D correctly defines INNER JOIN.
To answer this question, let's go through each option to understand why it is correct or incorrect:
Option A) Returns all the matching rows from 2 tables - This option is incorrect. The INNER JOIN clause returns only the rows that have matching values in the field on which the two tables are joined, not all matching rows from both tables.
Option B) Returns only the rows from the first table, which have non-matching values with the second table in the field on which the 2 tables are joined - This option is incorrect. The INNER JOIN clause returns only the rows with matching values, not non-matching values.
Option C) Returns all rows from 2 tables - This option is incorrect. The INNER JOIN clause only returns the rows that have matching values, not all rows from both tables.
Option D) Returns all rows that have matching value in the field on which the 2 tables are joined - This option is correct. The INNER JOIN clause returns all rows that have matching values in the field on which the two tables are joined.
The correct answer is D. This option is correct because the INNER JOIN clause is used to return all rows that have matching values in the field on which the two tables are joined.