Using mysqli_fetch_assoc in PHP to Retrieve Query Results

In PHP, database operations are essential, and using the mysqli extension is a common approach. This article introduces how to use the mysqli_fetch_assoc function to obtain query results.

1. Connect to the Database

First, we use the mysqli_connect function to establish a connection to a MySQL database. Below is a sample code:

$servername = "localhost";
$username = "root";
$password = "password";
$dbname = "myDB";

$conn = mysqli_connect($servername, $username, $password, $dbname);

// Check connection
if (!$conn) {
    die("Connection failed: " . mysqli_connect_error());
}

2. Query the Database

Next, we can use the mysqli_query function to execute an SQL statement. Example query:

$sql = "SELECT id, name, email FROM users";
$result = mysqli_query($conn, $sql);

After running the query, the mysqli_fetch_assoc function can fetch each row as an associative array. It returns the next row on each call until no rows remain.

while ($row = mysqli_fetch_assoc($result)) {
    echo "ID: " . $row["id"] . ", Name: " . $row["name"] . ", Email: " . $row["email"] . "
";
}

3. Full Example

The following complete example demonstrates using mysqli_fetch_assoc to retrieve query results:

$servername = "localhost";
$username = "root";
$password = "password";
$dbname = "myDB";

$conn = mysqli_connect($servername, $username, $password, $dbname);
if (!$conn) {
    die("Connection failed: " . mysqli_connect_error());
}

$sql = "SELECT id, name, email FROM users";
$result = mysqli_query($conn, $sql);

if (mysqli_num_rows($result) > 0) {
    while ($row = mysqli_fetch_assoc($result)) {
        echo "ID: " . $row["id"] . ", Name: " . $row["name"] . ", Email: " . $row["email"] . "
";
    }
} else {
    echo "0 results";
}

mysqli_close($conn);

Note: Replace the database name, table name, and credentials with those appropriate for your environment.

Conclusion

This article showed how to use mysqli_fetch_assoc to fetch query results by connecting to the database, executing a query, and iterating over the result set, enabling more efficient data handling in PHP development.