Error
Error Code:
3695
MySQL Error 3695: Look-behind Assertion Limit Exceeded
Description
This error indicates that a regular expression used in MySQL contains a look-behind assertion whose pattern length exceeds the internal limits of the database's regex engine. It typically occurs when the look-behind pattern is very long, complex, or uses unbounded quantifiers, making its exact length indeterminate or too large for the engine to process.
Error Message
The look-behind assertion exceeds the limit in regular expression.
Known Causes
3 known causesExcessive Look-behind Pattern Length
The literal string or pattern within the look-behind assertion is too long, exceeding the maximum byte length supported by MySQL's regex engine (RE2).
Unbounded Quantifiers in Look-behind
Using quantifiers like `*`, `+`, or `{n,}` within a look-behind assertion can lead to an indeterminate or excessively long pattern length, triggering the limit.
Complex or Nested Look-behinds
Deeply nested or highly complex look-behind structures, even if individual parts are short, can cumulatively exceed the internal length limits.
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