How to Select Data from Multiple Tables with Identical, Ambiguous Columns?-Mysql Tutorial-php.cn

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How to Select Data from Multiple Tables with Identical, Ambiguous Columns?

Barbara Streisand

Dec 29, 2024 pm 03:52 PM

How to Select Data from Multiple Tables with Identical, Ambiguous Columns?

Joining Tables with Ambiguous Columns: Selecting Data from Multiple Replicated Tables

Your challenge of retrieving data from multiple tables with an identical structure but separated for localization raises an ambiguity when specifying columns in a WHERE clause. MySQL cannot determine which table to reference when comparing an ambiguous column, such as 'genre' in your query.

Solution: Utilize the UNION Operator

To resolve this ambiguity, you can employ the UNION operator. UNION combines the results of two or more SELECT statements, effectively creating a virtual table with the union of all rows from the individual tables.

Modified Query:

Explanation:

This modified query separates the SELECT statements for each involved table. Each subquery retrieves data from a specific table, ensuring there is no ambiguity in the 'genre' column reference. The UNION operator then combines the results into a single result set, providing you with the desired data from multiple tables.

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