Programming Languages

PHP MySQL SELECT Queries

Retrieve data from MySQL database using SELECT

MySQLi Select (Procedural)

$sql = "SELECT * FROM users"; # SQL query
$result = mysqli_query($conn, $sql); # execute query
if (mysqli_num_rows($result) > 0) { # check if rows exist
    while($row = mysqli_fetch_assoc($result)) { # loop through results
        echo $row["name"]; # access column data
    }
}
mysqli_free_result($result); # free memory

MySQLi Select (OOP)

$sql = "SELECT id, name FROM users WHERE age > 18"; # query with condition
$result = $conn->query($sql); # execute query
if ($result->num_rows > 0) { # check row count
    while($row = $result->fetch_assoc()) { # fetch associative array
        echo $row["id"] .  "-"  . $row["name"]; # display data
    }
}

PDO Select

$sql = "SELECT * FROM users"; # SQL query
$stmt = $pdo->query($sql); # execute query
$users = $stmt->fetchAll(); # fetch all rows
foreach($users as $user) { # loop through results
    echo $user["name"]; # access data
}

Fetch Methods

$row = $stmt->fetch(); # fetch single row
$rows = $stmt->fetchAll(PDO::FETCH_ASSOC); # fetch all as array
$column = $stmt->fetchColumn(); # fetch single column