Why Does My PHP Code Throw \'mysqli_fetch_array() expects parameter 1 to be mysqli_result, boolean given\'?

"mysqli_fetch_array() expects parameter 1 to be mysqli_result, boolean given" Error: Troubleshooting in PHP

The "mysqli_fetch_array() expects parameter 1 to be mysqli_result, boolean given" error in PHP arises when the first parameter passed to mysqli_fetch_array() is not a valid result set from a successful MySQL query.

Problem:

In the provided code snippet, the query "SELECT * FROM users WHERE fb_id = " . $fb_id . " LIMIT 0, 30 " is not executing successfully. As a result, mysqli_query() returns false, which is then passed as the first parameter to mysqli_fetch_array(). This causes the error.

Solution:

To fix the error, you need to ensure that the MySQL query is valid and returns a valid result set. Add the following code after mysqli_query() to check for errors and display them:

if (!$check1_res) {
    trigger_error(mysqli_error($con), E_USER_ERROR);
}

This will output the error message if the query fails, helping you identify the issue.

Possible Causes:

• Database connection issues: Ensure that the database connection ($con) is valid.
• Syntax errors in the query: Check the query for any typos or incorrect syntax.
• Permission denied: Verify that the user has the necessary permissions to perform the query.
• Invalid table or field names: Make sure the table users and the field fb_id exist in the database.

Additional Information:

• For more information on mysqli_error(): https://www.php.net/manual/en/mysqli.error.php
• Refer to the MySQL documentation for guidelines on writing correct queries: https://dev.mysql.com/doc/

The above is the detailed content of Why Does My PHP Code Throw \'mysqli_fetch_array() expects parameter 1 to be mysqli_result, boolean given\'?. For more information, please follow other related articles on the PHP Chinese website!