How can PHP developers effectively debug and troubleshoot SQL queries that are not returning the expected results when using JOIN operations?

When SQL queries with JOIN operations are not returning the expected results, PHP developers can effectively debug and troubleshoot by checking the query syntax, ensuring the JOIN conditions are correct, and using tools like var_dump() to inspect the result set. Additionally, developers can echo out the generated SQL query to see if it matches their expectations and use SQL debugging tools to analyze the query execution. 

// Example PHP code snippet to debug and troubleshoot SQL queries with JOIN operations

// Define the SQL query with JOIN operations
$sql = "SELECT * FROM table1 JOIN table2 ON table1.id = table2.table1_id WHERE table1.column = 'value'";

// Output the generated SQL query for inspection
echo $sql;

// Execute the query and fetch the results
$result = mysqli_query($connection, $sql);

// Check if the query executed successfully
if($result){
    // Fetch and display the results
    while($row = mysqli_fetch_assoc($result)){
        var_dump($row);
    }
} else {
    // Display an error message if the query fails
    echo "Error executing query: " . mysqli_error($connection);
}

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