SQL Querying Multiple Tables: Difference between revisions

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=Join Condition=
If more than one table appears in the <code>FROM</code> 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.




Join condition


Foreign key
Foreign key


=Join=
=Join=

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