How to Resolve Discrepancy Between Variables and Parameters in Prepared Statements?

bind_param: Discrepancy between Variables and Parameters in Prepared Statement

Your code snippet encounters an error: "Number of variables doesn't match number of parameters in prepared statement." This indicates a mismatch between the variables in your bind_param() function and the placeholders (?) in your prepared statement.

To resolve this, ensure that your prepared statement accurately substitutes all variables with question marks. Remove the quotes around question marks, as seen in the corrected code below:

$stmt = $mysqli->prepare("
    SELECT DISTINCT model FROM vehicle_types WHERE year = ? AND make = ? ORDER by model
");
$stmt->bind_param('is', $year, $make);
$stmt->execute();

The number of question marks should always match the number of variables passed to bind_param(). In your original code, there were two variables ($year, $make) but only one question mark in the prepared statement, leading to the error.

Additionally, ensure that the data types of the variables match the data types of the database columns. For example, if the year column in the database is an integer, then $year should be cast as an integer before binding.

The above is the detailed content of How to Resolve Discrepancy Between Variables and Parameters in Prepared Statements?. For more information, please follow other related articles on the PHP Chinese website!