Using mysqli_fetch_assoc in PHP to Retrieve Rows as Associative Arrays

In PHP, interacting with a database is a common task. When we execute a SELECT query and obtain a result set, we usually need to store the data in a PHP array for further processing.

PHP provides several functions for handling result sets, and one frequently used function is mysqli_fetch_assoc. This function retrieves one row from the result set as an associative array, making it easy to access data by column name.

Below is a complete example that demonstrates how to use mysqli_fetch_assoc to fetch a row from a result set:

<?php<br/>// Connect to the database<br/>$mysqli = new mysqli("localhost", "username", "password", "database");<br/><br/>// Check connection<br/>if ($mysqli->connect_errno) {<br/>    echo "Failed to connect to MySQL: " . $mysqli->connect_error;<br/>    exit();<br/>}<br/><br/>// Execute SELECT query<br/>$result = $mysqli->query("SELECT * FROM users");<br/><br/>// Verify that rows were returned<br/>if ($result->num_rows > 0) {<br/>    // Fetch one row as an associative array<br/>    $row = mysqli_fetch_assoc($result);<br/><br/>    // Output the values<br/>    echo "ID: " . $row['id'] . "<br>";<br/>    echo "Name: " . $row['name'] . "<br>";<br/>    echo "Age: " . $row['age'] . "<br>";<br/>} else {<br/>    echo "No data found.";<br/>}<br/><br/>// Close the connection<br/>$mysqli->close();<br/>?>

In the example, the query result is stored in $result. The call mysqli_fetch_assoc($result) returns a single row, which we store in $row. The $row array can then be accessed by field names such as 'id', 'name', and 'age'.

It is important to note that each call to mysqli_fetch_assoc returns the next row in the result set; when no more rows are available, it returns null. Therefore, to retrieve multiple rows you would typically place the call inside a loop.

Using mysqli_fetch_assoc simplifies handling database query results, improves code readability, and enhances maintainability.

In summary, the provided example shows how to use the PHP function mysqli_fetch_assoc to fetch a row from a result set as an associative array, which can be very helpful during development.