Why Am I Getting MySQL Error 1022 When Creating a Table with Foreign Keys?

MySQL Error 1022: Unveiling the Root Cause

Creating tables is a fundamental aspect of database design, but sometimes, unexpected errors can arise. One such error is the infamous MySQL Error 1022, which often occurs when attempting to create a table with duplicate keys.

In a recent case, a user encountered this error while using MySQL Workbench to create the 'errors_reports' table. Despite the table appearing valid, MySQL obstinately refused to comply, citing the presence of duplicate keys.

Search for the Incriminating Key

Unable to locate the troublesome key visually, the user painstakingly eliminated elements of the table definition, ultimately isolating the culprit: a foreign key constraint referencing the 'errors' table.

The Curious Case of Identical Foreign Keys

Strangely, the user had encountered identical foreign key definitions in other tables without issue. However, in this instance, MySQL refused to tolerate the duplication.

Unmasking the Conflict

The solution to this perplexing dilemma lies in the concept of foreign key naming conventions. As it turns out, foreign keys cannot share the same name within a database. This is because MySQL utilizes foreign key names to determine which table and column the reference points to. Assigning the same name to multiple foreign keys can lead to confusion and ambiguity.

A Clearer Path to Table Creation

To resolve the error and successfully create the 'errors_reports' table, the user adjusted the name of the offending foreign key. By ensuring that foreign key names were unique, the user satisfied MySQL's naming convention and paved the way for a successful table creation.

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