SQL Querying Multiple Tables

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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