Warning
Error Code:
1739
MariaDB Error 1739: Index Inefficiency from Type/Collation Conversion
Description
This error indicates that the MariaDB optimizer cannot utilize an index for a query due to a mismatch in data types or collations between the indexed column and the values or columns used in the query's WHERE clause or JOIN conditions. This typically forces a full table scan, significantly impacting query performance and acting as a warning about sub-optimal query execution.
Error Message
Cannot use %s access on index '%s' due to type or collation conversion on field '%s'
Known Causes
3 known causesMismatched Data Types in Comparisons
The data type of an indexed column differs from the data type of the value or column it's being compared against in a query, triggering a type conversion.
Conflicting Collations for String Fields
String comparisons involve an indexed column and a literal or another column that uses a different character set or collation, requiring a collation conversion.
Implicit Type Coercion on Indexed Field
MariaDB implicitly converts the data type of an indexed column to match the type of the comparison value, which bypasses the index's efficiency.
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