When MySQL deletes a foreign key, the Operation prompts "error121". solution:

Environment: MySQLServer5.1 + NavicatforMysql8.2 problem: a 121 error occurs when the foreign key is deleted. Solution: Change the foreign key name to another name. Error Message

Environment: MySQL Server 5.1 + Navicat for Mysql 8.2 problem: a 121 error occurs when the foreign key is deleted. Solution: Change the foreign key name to another name. Error Message

Environment: MySQL Server 5.1 + Navicat for Mysql 8.2

Problem: A 121 error occurred while deleting the foreign key.

Solution:

Change the foreign key name to another name.

For error information, refer:

Error 121

This is an error where the names of external keywords are repeated. Even in different tables, the names of external keywords cannot be repeated.

Error 150

There are three types of errors:
1. The types of foreign keys and referenced Foreign keys are different, such as integer and double;
2. The column to be referenced cannot be found;
3. The character encoding of the table is different.

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