从多个表中获取具有相同名称的列

Question

i have two tables: USERS(id, name, email, password) QUESTIONS(id, userid, type, ques, date, time)

i have to pass the value of questions.id as qid. i am unable to get the desired result with the following code. instead of taking 'id' value of QUESTIONS table, it is taking the 'id' value of USERS table, and therby producing wrong output.

$query = "
SELECT *
     , q.id qid 
  FROM questions q
  JOIN users u
    ON u.id = q.userid 
 WHERE type = 'technical' 
 ORDER 
    BY date
     , time DESC
 ";
$result = mysqli_query($conn,$query);
while ($row = mysqli_fetch_array($result)) {

$id = $_SESSION['id'];  
$ques=$row['question'];
$user = $row['username'];

    echo strtoupper($user);

    echo "<a href='allview.php?qid=$row[id]' class='class4'> $ques </a>";

}
?>

Answer 1

This code:

$id = $_SESSION['id'];  

Refers to the id column in the select . That id comes from the users table.

You have renamed the question id to qid , so try:

$qid = $_SESSION['qid'];

A word of advice: only fetch the columns you are actually going to use:

SELECT u.username, q.id as qid
FROM questions q JOIN
     users u
     ON u.id = q.userid
WHERE type = 'technical' 
ORDER BY date, time DESC;

The * is handy when debugging, but the code could end up behaving unexpectedly at some point because the underlying table structure changes.

Answer 2

Try to use this code

$query = "
SELECT *
     , q.id AS qid,
       q.id AS id
  FROM questions q

Answer 3

Try using this

$query = "
SELECT *
     , questions.id qid 
  FROM questions q
  , users u
 WHERE q.userid = u.id
 AND type = 'technical' 
 ORDER 
    BY date
     , time DESC
 ";