The mysqli_fetch_row() function in PHP retrieves a result row from a MySQLi result set as a numeric array. This function is part of the MySQLi extension and is used in procedural style to fetch data from a query result.

Syntax

mysqli_fetch_row(result)

Parameters

• result: The mysqli_result object returned by mysqli_query() when executing a SELECT query. This object represents the result set from the query.

Return Values

• On success: Returns a numeric array where each element corresponds to a column value in the row. The indices of the array start from 0, corresponding to the column positions.
• On failure: Returns null when there are no more rows to fetch (i.e., when all rows have been retrieved).

Example Usage

Here’s a step-by-step example demonstrating how to use mysqli_fetch_row():

1. Establish a Database Connection

<?php
// Connect to the database
$conn = mysqli_connect('localhost', 'username', 'password', 'database');

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

2. Execute a SELECT Query

// Prepare and execute a SELECT query
$sql = "SELECT username, email FROM users";
$result = mysqli_query($conn, $sql);

3. Fetch and Display Rows

if ($result) {
    // Fetch rows one by one
    while ($row = mysqli_fetch_row($result)) {
        // Access data using column indices
        echo "Username: " . $row[0] . " - Email: " . $row[1] . "<br>";
    }

    // Free the result set
    mysqli_free_result($result);
} else {
    echo "Error: " . mysqli_error($conn);
}

4. Close the Database Connection

// Close the connection
mysqli_close($conn);
?>

How It Works

• Fetching Rows: Each call to mysqli_fetch_row() retrieves the next row from the result set. It returns the row as a numeric array, with column values accessed using numeric indices.

• Array Indices: The array indices correspond to the positions of the columns in the result set, starting from 0. For example, the first column value is accessed with $row[0], the second with $row[1], and so on.

• End of Result Set: When there are no more rows to fetch, mysqli_fetch_row() returns null.

• Freeing Result Set: After processing the result set, use mysqli_free_result() to free the memory associated with it.

Notes

• Numeric Indexes: mysqli_fetch_row() is useful when you want to access data by column index rather than by column name.
• Performance: Fetching rows as numeric arrays can be slightly faster than fetching them as associative arrays because there is no overhead of creating associative keys.