When working with JOIN statements in PHP to retrieve data from multiple tables, what are some common pitfalls to avoid?

One common pitfall when working with JOIN statements in PHP is forgetting to specify the columns to select from each table, which can result in ambiguous column names and unexpected results. To avoid this, always alias columns with table names in the SELECT statement to make them unique. 

// Example of specifying columns with table aliases in a JOIN statement
$query = "SELECT users.id AS user_id, orders.id AS order_id
          FROM users
          JOIN orders ON users.id = orders.user_id";
$result = mysqli_query($connection, $query);

// Loop through the results
while($row = mysqli_fetch_assoc($result)) {
    echo "User ID: " . $row['user_id'] . ", Order ID: " . $row['order_id'] . "<br>";
}

Keywords

JOIN statements PHP multiple tables data retrieval common mistakes

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