Error
Error Code:
1688
MariaDB Error 1688: Index Comment Exceeds Length Limit
Description
This error indicates that the `COMMENT` attribute provided for a database index (e.g., during `CREATE TABLE`, `ALTER TABLE`, or `CREATE INDEX` operations) has exceeded MariaDB's maximum allowed byte length. MariaDB imposes a specific byte limit on the length of index comments, and attempting to use a longer string will prevent the DDL statement from executing successfully.
Error Message
Comment for index '%s' is too long (max = %lu)
Known Causes
3 known causesExplicitly Long Index Comment
A `COMMENT` attribute for an index definition was manually provided with a string that surpasses the maximum allowed byte length in MariaDB.
ORM or Tool-Generated Comment
An Object-Relational Mapper (ORM) or a database design tool automatically generated an index comment that is too verbose for MariaDB's configured limit.
Multi-Byte Character Encoding
When using multi-byte character sets (e.g., UTF-8), a seemingly short comment string can consume more bytes than expected, causing it to exceed the byte-based length limit.
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