Passing variables without a form using url - php

Question

I have been trying to find information on passing variables without a form using url, but I can't seem to find anythig that pertains to my situation.
Basically I need to have a page that is hierachical in the sense that you can click one course out of a list, that brings you to a list of sections, and you can click on a section which will bring to a page with the correct information for that one section. I was taught for this situation to use $_SESSION and then to include the variables in the url. My problem is that everytime I click on a course or a section, the information for every single course or section that is a query match is displaying rather than just the information for that one course or section. This is what I have for each of the pages in hierarchical order (not including the connect portion of the code which works fine anyways). I know this is a ton of code, and a complete mess. I will keep searching out information, and many many thanks in advance for any help.
List of Courses
session_start();
$section = $_SESSION['section_id'];
$user_fname = $_SESSION['user_fname'];
$user_lname = $_SESSION['user_lname'];
$query = "SELECT DISTINCT course_t.course_id, course_name, user_fname, user_lname, section_t.section_id
FROM course_t, authorized_user_t, section_t, teaching_history_t
WHERE authorized_user_t.authorized_user_id = teaching_history_t.instructor_id
AND teaching_history_t.section_id = section_t.section_id
AND section_t.course_id = course_t.course_id";
$result = #mysql_query($query);
while ($line1 = mysql_fetch_array($result, MYSQL_ASSOC)) {
echo '<p align = "center"><strong>' .$line1['course_id'].':'.$line1['course_name']. '</strong><br><br>';
}
List of Sections (it is supposed to list a single intructor and then each of the sections they teach under their name)
session_start();
$section_id = $_REQUEST['section_id'];
$user_fname = $_REQUEST['user_fname'];
$user_lname = $_REQUEST['user_lname'];
$course_id = $_SESSION['course_id'];
$course_name = $_SESSION['course_name'];
$section_id = $_SESSION['section_id'];
$semester = $_SESSION['semester'];
$year = $_SESSION['year'];
$course_description = $_SESSION['course_description'];
$SGoal_Description = $_SESSION['SGoal_Description'];
$sobjective_description = $_SESSION['sobjective_description'];
$LObjective_Description = $_SESSION['LObjective_Description'];
$topic_title = $_SESSION['topic_title'];
$topic_description = $_SESSION['topic_description'];
$coursework_title = $_SESSION['coursework_title'];
$coursework_location = $_SESSION['coursework_location'];
$coursework_description = $_SESSION['coursework_description'];
$query = "SELECT course_t.course_id, course_name, section_t.section_id, semester, year, course_description,
SGoal_Description, sobjective_description, LObjective_Description, topic_title, topic_description, coursework_title,
coursework_location, coursework_description, syllabus
FROM course_t, section_t, section_goal_section_t, section_goal_t, section_coursework_t,
mapped_topic_section_t, mapped_lis_section_t, coursework_t, topic_t, lis_objective_t, section_objective_t
WHERE course_t.course_id = section_t.course_id
AND section_t.section_id = section_goal_section_t.section_id
AND section_goal_section_t.sgoal_id = section_goal_t.sgoal_id
AND section_goal_section_t.section_id = mapped_lis_section_t.section_id
AND mapped_lis_section_t.lobjective_id = lis_objective_t.lobjective_id
AND section_t.section_id = mapped_topic_section_t.section_id
AND mapped_topic_section_t.topic_id = topic_t.topic_id
AND section_t.section_id = section_coursework_t.section_id
AND mapped_lis_section_t.sobjective_id = section_objective_t.sobjective_id
AND section_coursework_t.coursework_id = coursework_t.coursework_id";
$result = #mysql_query($query);
while ($line1 = mysql_fetch_array($result, MYSQL_ASSOC)) {
echo '<ul align = "center"<strong>' .'Instructor'. ':' ."$user_fname". "$user_lname".'<li align = "center">
<a href ="course_section.php?course_id='.$line1['course_id'].'&course_name='.$line1['course_name'].'&section_id='.$line1['section_id'].'
&semester='.$line1['semester'].'&year='.$line1['year'].'&course_description='.$line1['course_description'].'
&SGoal_Description='.$line1['SGoal_Description'].'&sobjective_description='.$line1['sobjective_description'].'
&LObjective_Description='.$line1['LObjective_Description'].'&topic_title='.$line1['topic_title'].'
&topic_description='.$line1['topic_description'].'&coursework_title='.$line1['coursework_title'].'
&coursework_location='.$line1['coursework_location'].'&coursework_description='.$line1['coursework_description'].'">'.$line1['section_id'].'</a></strong><br><br>';
}
Section Information (should display information for the section that is clicked on)
session_start();
$topic_description = $SESSION['topic_description'];
$coursework_description = $SESSION['coursework_description'];
$course_id = $_REQUEST['course_id'];
$course_name = $_REQUEST['course_name'];
$section_id = $_REQUEST['section_id'];
$semester = $_REQUEST['semester'];
$year = $_REQUEST['year'];
$course_description = $_REQUEST['course_description'];
$SGoal_Description = $_REQUEST['SGoal_Description'];
$sobjective_description = $_REQUEST['sobjective_description'];
$LObjective_Description = $_REQUEST['LObjective_Description'];
$topic_title = $_REQUEST['topic_title'];
$topic_description = $_REQUEST['topic_description'];
$coursework_title = $_REQUEST['coursework_title'];
$coursework_location = $_REQUEST['coursework_location'];
$coursework_description = $_REQUEST['coursework_description'];
echo '<div align = "right">';
echo 'Return to List of Sections';
echo '</div>';
$query = "SELECT DISTINCT course_t.course_id, course_name, section_t.section_id, semester, year, course_description,
SGoal_Description, sobjective_description, LObjective_Description, topic_title, topic_description, coursework_title,
coursework_location, coursework_description, syllabus
FROM course_t, section_t, section_goal_section_t, section_goal_t, section_coursework_t,
mapped_topic_section_t, mapped_lis_section_t, coursework_t, topic_t, lis_objective_t, section_objective_t
WHERE course_t.course_id = section_t.course_id
AND section_t.section_id = section_goal_section_t.section_id
AND section_goal_section_t.sgoal_id = section_goal_t.sgoal_id
AND section_goal_section_t.section_id = mapped_lis_section_t.section_id
AND mapped_lis_section_t.lobjective_id = lis_objective_t.lobjective_id
AND section_t.section_id = mapped_topic_section_t.section_id
AND mapped_topic_section_t.topic_id = topic_t.topic_id
AND section_t.section_id = section_coursework_t.section_id
AND mapped_lis_section_t.sobjective_id = section_objective_t.sobjective_id
AND section_coursework_t.coursework_id = coursework_t.coursework_id";
$result = #mysql_query($query);
while ($line1 = mysql_fetch_array($result, MYSQL_ASSOC)) {
echo '<p align = "center"><strong>' .$line1['course_id'].':'.' '.$line1['course_name']. '</strong><br><br>';
echo '<p align = "center"><strong>' .$line1['section_id'].':'.' '.$line1['semester'].'/'.$line1['year']. '</strong><br><br>';
echo '<p align = "left"><strong>' .$line1['course_description'].'</strong><br><br><br><br>';
echo '<div align = "left">';
echo '<ul align = "left"><strong>Section Goals:</strong></ul><li align = "left">' .$line1['SGoal_Description']. '</li>';
echo '<ul align = "left"><strong>Section Objectives:</strong></ul><li align = "left">' .$line1['sobjective_description']. '</li>';
echo '<ul align = "left"><strong>Mapped Objectives:</strong></ul><li align = "left">' .$line1['LObjective_Description']. '</li>';
echo '<ul align = "left"><strong>'.'Topic'.':'.' '.$line1['topic_title']. '</strong></ul>
<li align = "left">Click for Topic Description';
echo '<ul align = "left"><strong>'.'Coursework'.':'.' '.$line1['coursework_title']. '</strong></ul>
<li align = "left">Click for Coursework Description';
}

Answer 1

Don't use sessions, just include it in the url ex: example.com/index.php?example=true. If you use $_GET['example'] it will have the value 'true'.