Error
Error Code:
3174
MySQL Error 3174: Foreign Key on Indexed Virtual Column Base Conflict
Description
This error occurs when you attempt to create a foreign key constraint on a column that is already serving as the base for an *indexed virtual column*. MySQL prevents this configuration to avoid complex dependencies and potential data integrity issues, as modifications to the base column would affect both the foreign key relationship and the indexed virtual column's value.
Error Message
Cannot add foreign key on the base column of indexed virtual column.
Known Causes
3 known causesDirect Foreign Key Creation Attempt
You tried to add a foreign key constraint directly on a column that is already the base for an existing indexed virtual column.
Schema Design Conflict
Your database schema design inadvertently designates a column for both foreign key relationships and as a base for an indexed virtual column.
Automated DDL Generation
An ORM or schema migration tool generated DDL that attempts to create this disallowed foreign key configuration.
Solutions
Coming SoonDetailed step-by-step solutions for this error are being prepared. In the meantime, try these general troubleshooting tips:
General Troubleshooting Tips
- Check the error message carefully for specific details
- Review recent changes that might have caused the error
- Search for the exact error code in the official documentation
- Check log files for additional context
- Try restarting the application or service