How to Resolve 'Ambiguous Column' Errors When Joining Tables with Identical Structures?

Resolving Ambiguous Column References When Joining Tables with Identical Structures

In the realm of database management, it's not uncommon to encounter situations where multiple tables share the same data structure but differ in their content. When working with such tables and attempting to retrieve data based on a specific column, you may encounter an "ambiguous column" error, as in the case described in the given query.

The primary challenge arises when you attempt to join these tables using a common column like 'genre' without specifying the table name in the WHERE clause. Since both tables contain a column named 'genre,' MySQL cannot identify which table's column to use for comparison.

The solution lies in using the UNION operator, which combines the result sets of two or more SELECT statements into a single result set. By enclosing each SELECT statement in parentheses and using UNION, you can merge the records from each table that satisfy the 'genre' = 'punk' condition.

The resulting query would look like this:

(SELECT * FROM us_music WHERE `genre` = 'punk')
UNION
(SELECT * FROM de_music WHERE `genre` = 'punk')

This approach allows you to selectively retrieve data from multiple tables with the same structure while specifying the table name in the WHERE clause, resolving the ambiguity and enabling the desired sorting based on the 'genre' column.

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