Why Does My MySQL Prepared Statement Fail with a \'Number of elements in type definition string doesn\'t match number of bind variables\' Error?

The Mystery of the Mismatched Bind Variables

The question revolves around an error encountered when binding parameters for an extensive MySQL prepared statement. The issue lies with the mismatch between the number of "s" type indicators in the bind_param method and the number of question marks (?) in the query string.

Understanding bind_param()

bind_param() is a mysqli method that replaces question marks (?) in a prepared query with actual data. Each character in the type definition string (e.g., "s" for string) corresponds to a question mark and the data to be bound.

Matching the Number of Bind Variables

The critical point to remember is that the number of characters in the type definition string (e.g., "s,s,s") must precisely match the number of question marks (?) in the query string. For instance, a query with 3 question marks requires a type definition string with 3 "s" characters.

Examining the Code

In the given PHP code, the query string contains 65 question marks, but the bind_param() method uses "s,s,s,s,s,s,s,s" (a total of only 8 "s" characters). This discrepancy leads to the error message: "Number of elements in type definition string doesn't match number of bind variables."

To Resolve the Issue:

To rectify the issue, verify that the number of "s" characters in the bind_param() method matches the number of question marks (?) in the query string. In this case, the bind_param() method should be replaced with:

$stmt->bind_param("sssssssssssssssssssssssssssssssssssssssssssssssssssssssssss", ...);

Additional Notes:

• Characters in the type definition string should not be separated by commas.
• The format described in the manual page for mysqli_stmt::bind_param() should be followed.

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