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<html>
	<meta http-equiv="Content-Type" content="text/html; charset=UTF-8" />

<?php

	//вытащить все студенты по номеру группы -- lab 2
	$servername = "localhost";
	$username = "user";
	$password = "user";
	$dbname = "xxx";
	// Create connection
	$conn = new mysqli($servername, $username, $password, $dbname);
	// Check connection
	if ($conn->connect_error) {
	    die("Connection failed: " . $conn->connect_error);
	}
	else {

		//dump from students, not results

		$group = intval($_POST['Groups_dropdown']);  // Storing Selected Value In Variable
		if ($group == 0)
			echo "You have selected all students <br />";
		else
			echo "You have selected :" .$group . "<br />"; // Displaying Selected Value

		echo "<table>";
		echo "<tr>";
		echo "<td>Student id</td>";
		echo "<td>Last name</td>";
		echo "<td>First name</td>";
		echo "<td>Second name</td>";
		echo "<td>Group</td>";
		echo "</tr>";

		//$group = $_POST['get_group'];
		$sql = "SELECT * FROM students"; //all results
		$results_data = $conn->query($sql);


		if ($results_data->num_rows > 0)
		{
			while($results = $results_data->fetch_assoc() ) //while results != 0
			{

				$temp = $results["group_number"];//students group number
				$sql = "SELECT * FROM groups WHERE groups.id='$temp'";
				$results_data_groups = $conn->query($sql);
				$results_groups = $results_data_groups->fetch_assoc();

				if ($group == 0) {
					echo "<tr>";
					echo "<td>" .$results["id"]. "</td>";
					echo "<td>" .$results["last_name"]. "</td>";
					echo "<td>" .$results["first_name"]. "</td>";
					echo "<td>" .$results["second_name"]. "</td>";
					echo "<td>" .$results_groups["group_name"]. "</td>";
					echo "</tr>";

				}
				else if ($results_groups["group_name"] == $group)
				{

		    		echo "<tr>";
					echo "<td>" .$results["id"]. "</td>";
					echo "<td>" .$results["last_name"]. "</td>";
					echo "<td>" .$results["first_name"]. "</td>";
					echo "<td>" .$results["second_name"]. "</td>";
					echo "<td>" .$results_groups["group_name"]. "</td>";
					echo "</tr>";

		    	}
		    }//while
		    echo "</table><br />";
	    }//if
	 	else
	 	{
	 		echo "0 results";
	 	}
	}
	$conn->close();
?>

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