How Can I Efficiently Query Multiple Tables with Identical Structures in MySQL?

Querying Multiple Tables with Identical Structure: MySQL

When working with databases, it is common to encounter tables with identical data structures but distinct data. This can arise due to factors such as localization or data sharding. Retrieving data across such tables can present challenges, particularly when sorting the results based on specific user-defined columns.

One common issue arises when using a simple SELECT statement to join data from multiple tables, as seen in the example provided. MySQL interprets this query as an ambiguous join, as it cannot determine which table's genre column should be used for the filtering condition.

The solution lies in utilizing MySQL's UNION operator. The UNION clause allows you to combine the results of multiple SELECT statements into a single result set. In this case, you can use UNION to append the results from each table into a single sorted result set:

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

By using UNION, you can retrieve data across multiple tables while applying a common filtering condition and maintaining the desired sorting order.

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