SQL: Difference between revisions

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=Overview=
=Overview=
This article documents standard SQL. For database-specific extensions, we'll link to the database DML operations page.


=<tt>SELECT</tt>=
=<tt>SELECT</tt>=

Revision as of 16:48, 22 May 2024

Internal

Overview

This article documents standard SQL. For database-specific extensions, we'll link to the database DML operations page.

SELECT

JOIN Clause

A SELECT JOIN clause is using to query and access rows from two or more tables by establishing a logical relationship between those rows. The relationship is based on common field values, specified in the JOIN clause with the keyword ON.

WHERE Clause

JOIN

The SQL JOIN clause is used to combine rows from two or more tables, based on a related column between them.

INNER JOIN

Return records that have matching values in both tables.

LEFT (OUTER) JOIN

Return all records from the left table and the matching records from the right table.

RIGHT (OUTER) JOIN

Return all records from the right table and the matching records from the left table.

FULL (OUTER) JOIN

Returns all records when there is a match in either left or right table.