


Why Does My PHP Code Throw a Fatal 'mysqli_sql_exception: No Index Used' Error?
Fatal Error: Uncaught Exception 'mysqli_sql_exception' with Message 'No Index Used in Query/Prepared Statement'
This error occurs when attempting to execute a query without an index used on the tables involved. While MySQL displays a warning indicating this issue, the true error lies in the PHP code itself due to the following factors:
- Excessive Warnings from mysqli: MySQL generates numerous warnings that are often benign.
- Throwing Exceptions for All Errors: PHP's mysqli_report(MYSQLI_REPORT_ALL) setting triggers exceptions not only for errors but also for warnings.
- Uncaught Exceptions: The PHP code fails to handle exceptions properly, resulting in a fatal error since uncaught exceptions are fatal.
To resolve this issue, you can either:
- Alter mysqli_report Settings: Change mysqli_report(...) to MYSQLI_REPORT_STRICT or MYSQLI_REPORT_OFF to ignore warnings.
- Use Try-Catch Blocks: Implement proper error handling by enclosing your code in try{} blocks and catching exceptions using catch(){} blocks.
By addressing these issues, you can ensure that PHP errors are handled correctly and avoid unnecessary fatal errors related to index usage.
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