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