How can MySQL queries be properly executed in PHP to avoid errors like multiple queries in a single mysql_query() call?

To avoid errors like multiple queries in a single mysql_query() call, you should use the mysqli_multi_query() function in PHP to execute multiple queries in a single call. This function allows you to execute multiple queries separated by semicolons in a single string. 

// Connect to MySQL database
$mysqli = new mysqli("localhost", "username", "password", "database");

// Check connection
if ($mysqli->connect_error) {
    die("Connection failed: " . $mysqli->connect_error);
}

// Multiple queries separated by semicolons
$sql = "SELECT * FROM table1; SELECT * FROM table2";

// Execute multiple queries
if ($mysqli->multi_query($sql)) {
    do {
        // Store and process the result set
        if ($result = $mysqli->store_result()) {
            while ($row = $result->fetch_assoc()) {
                // Process each row
            }
            $result->free();
        }
    } while ($mysqli->next_result());
} else {
    echo "Error executing multiple queries: " . $mysqli->error;
}

// Close connection
$mysqli->close();

Keywords

MySQL queries PHP mysqli_multi_query error prevention

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