SQL Querying Multiple Tables: Difference between revisions

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=Overview=
=Overview=
More than one table can be used in a <code>[[SQL_SELECT#Querying_Multiple_Tables|FROM]]</code> query clause, and when that happens, it is said that the query performs a '''join'''.
More than one table can be used in a <code>[[SQL_SELECT#Querying_Multiple_Tables|FROM]]</code> query clause, and when that happens, it is said that the query performs a '''join'''.


=Join Condition=
=Join Condition=

Revision as of 19:57, 23 May 2024

External

Internal

Overview

More than one table can be used in a FROM query clause, and when that happens, it is said that the query performs a join.

Join Condition

If more than one table appears in the FROM clause, then the condition used to link the tables must be included as well. This is the ANSI-approved method. of joining multiple tables, and it is the most portable across various database servers.


Foreign key

Join