I need help at getting data from MySQL Database. Right now I have a query that gives me:
Tournament ID
Tournament Name
Tournament Entry fee
Tournament Start and End date
For tournaments I am registered in. Now I want, for each tournament I am registered in, to count how many users are in that tournament, my points in that tournament, etc.
That info is in table called 'ladder'
ladder.id
ladder.points
ladder.userFK
ladder.tournamentFK
Database: http://prntscr.com/99fju1
PHP CODE for displaying tournaments I am registered in:
<?php
include('config.php');
$sql = "SELECT distinct tournaments.idtournament, tournaments.name, tournaments.entryfee, tournaments.start, tournaments.end
from tournaments join ladder
on tournaments.idtournament= ladder.tournamentFK and ladder.userFK=".$_SESSION['userid']."
group by tournaments.idtournament";
$result = $conn->query($sql);
if($result->num_rows > 0){
while($row = $result->fetch_assoc()) {
$tournament="<li class='registered' data-id=".$row['idtournament']." data-entryfee=".$row['entryfee']." data-prize=".$tournamentPrize."><span class='name'>".$row['name']."</span><span class='entry-fee'>Entry fee: ".$row['entryfee']."€</span><span class='prize-pool'>Prize pool: €</span><span class='date-end'>".$row['start']."-".$row['end']."</span><span class='btns'><button>Standings</button></span></li>";
echo $tournament;
}
}
$conn->close();
?>
Usually you can combine JOIN, COUNT() and GROUP BY in your query.
Some examples:
MySQL joins and COUNT(*) from another table
This would be the query I think.Change column and table name if its not correct. Not tested but I am sure this will give you some idea to make required query
select count(ladder.tournamentId)as userCount,tournaments.name
from
ladder left join tournaments
on ladder.tournamentId = tournaments.id
where ladder.tournamentId in
(
select tournaments.id from
tournaments left join ladder
on ladder.tournamentId = tournaments.id
where ladder.userId='yourId'
) and ladder.userId <> 'yourId'
group by ladder.tournamentId
Related
I'm working on a system, and this module is supposed to echo the contents of the database.
It worked perfectly until I added some JOIN statements to it.
I've checked and tested the SQL code, and it works perfectly. What's not working is that part where I echo the content of the JOINed table.
My code looks like this:
$query = "SELECT reg_students.*, courses.*
FROM reg_students
JOIN courses ON reg_students.course_id = courses.course_id
WHERE reg_students.user_id = '".$user_id."'";
$result = mysqli_query($conn, $query);
if (mysqli_fetch_array($result) > 0) {
while ($row = mysqli_fetch_array($result)) {
echo $row["course_name"];
echo $row["course_id"];
The course_name and course_id neither echo nor give any error messages.
UPDATE: I actually need to increase the query complexity by JOINing more tables and changing the selected columns. I need to JOIN these tables:
tutors which has columns: tutor_id, t_fname, t_othernames, email, phone number
faculty which has columns: faculty_id, faculty_name, faculty_code
courses which has columns: course_id, course_code, course_name, tutor_id, faculty_id
I want to JOIN these tables to the reg_students table in my original query so that I can filter by $user_id and I want to display: course_name, t_fname, t_othernames, email, faculty_name
I can't imagine that the user_info table is of any benefit to JOIN in, so I'm removing it as a reasonable guess. I am also assuming that your desired columns are all coming from the courses table, so I am nominating the table name with the column names in the SELECT.
For reader clarity, I like to use INNER JOIN instead of JOIN. (they are the same beast)
Casting $user_id as an integer is just a best practices that I am throwing in, just in case that variable is being fed by user-supplied/untrusted input.
You count the number of rows in the result set with mysqli_num_rows().
If you only want to access the result set data using the associative keys, generate a result set with mysqli_fetch_assoc().
When writing a query with JOINs it is often helpful to declare aliases for each table. This largely reduces code bloat and reader-strain.
Untested Code:
$query = "SELECT c.course_name, t.t_fname, t.t_othernames, t.email, f.faculty_name
FROM reg_students r
INNER JOIN courses c ON r.course_id = c.course_id
INNER JOIN faculty f ON c.faculty_id = f.faculty_id
INNER JOIN tutors t ON c.tutor_id = t.tutor_id
WHERE r.user_id = " . (int)$user_id;
if (!$result = mysqli_query($conn, $query)) {
echo "Syntax Error";
} elseif (!mysqli_num_rows($result)) {
echo "No Qualifying Rows";
} else {
while ($row = mysqli_fetch_assoc($result)) {
echo "{$row["course_name"]}<br>";
echo "{$row["t_fname"]}<br>";
echo "{$row["t_othernames"]}<br>";
echo "{$row["email"]}<br>";
echo "{$row["faculty_name"]}<br><br>";
}
}
I want to get some statitics out for my adminpanel.
I have two tables named users and cms_prosjekt. I want to count how many projects
that have the same attribute as users.
Each user have a motto that is connected to a project.
For example: Motto is spirit and the project code is spirit. It won't return anything. I have two users with the same motto as code in a project.
<?php
$result = mysql_query("SELECT
users.id,
COUNT(users.motto) AS count
FROM
users
LEFT JOIN cms_prosjekt ON
users.motto=cms_prosjekt.code
GROUP BY
users.motto");
$num_rows = mysql_num_rows($result);
echo "$num_rows";
?>
The query should be count(*) and group by user.motto
"SELECT
user.motto
, COUNT( * ) AS count
FROM users
LEFT JOIN cms_prosjekt ON users.motto=cms_prosjekt.code
GROUP BY users.motto"
The group by should be users.id not users.motto :
<?php
$result = mysql_query("SELECT users.id, COUNT(users.motto) AS count FROM users LEFT JOIN cms_prosjekt ON users.motto=cms_prosjekt.code GROUP BY (users.id)");
$num_rows = mysql_num_rows($result);
echo $num_rows;
?>
Note : i can't see any value for the left join you don't need any data from cms_prosjek but i keep it if you will use it later
I found the solution, but now I want to add a specific user id to the query. Since every administrator have their own home area, I want to list all the users that is connected to a specific administrator. Each administrator is creating projects with users.
I tried this:
$result = mysql_query("SELECT users.motto, COUNT( * ) AS count FROM users
WHERE id = '".$_SESSION['user']['id']."'
LEFT JOIN cms_prosjekt ON users.motto=cms_prosjekt.code
GROUP BY users.motto");
Here is my code:
<?php
$data = mysql_query("SELECT * FROM board") or die(mysql_error());
while($info = mysql_fetch_assoc( $data ))
{
if(!empty($info['user'])){
Print "".$info['user'].""; }
else {
}
myOtherQuery($info['id']);
}
function myOtherQuery($id) {
$result3 = mysql_query("SELECT COUNT(source_user_id) FROM likes
INNER JOIN pins ON pins.id = likes.pin_id
WHERE pins.board_id='$id'");
$c = mysql_result($result3, 0); // Cumulative tally of likes for board
{
Print "$c";
}
}
?>
The first part gets a users name and board details (board as in a photo album).
the second part joins that data with another sql table that counts the number of likes that board has.
Both are displayed as a name and a score represented by a number.
By default they are ordered by the date of creation. I'd like to be able to order them by the score. However, since the score is determined in the second part of the code, I don't know how to achieve it. Is it possible?
The solution is of course to query both at once in the first place, via a LEFT JOIN against a subquery returning the count per board_id:
SELECT
board.*,
/* Your PHP code will retrieve the likes count via this alias `numlikes` as in $info['numlikes'] */
numlikes
FROM
board
LEFT JOIN (
/* Subquery returns count per board_id */
SELECT pins.board_id, COUNT(source_user_id) AS numlikes
FROM
likes
INNER JOIN pins ON pins.id = likes.pin_id
GROUP BY pins.board_id
) likes ON board.id = likes.board_id
ORDER BY numlikes
It is nearly always significantly more efficient to perform a single query rather than n queries in a loop. You should strive to do so whenever possible.
You can do it in one query
SELECT board.*, count(likes.source_user_id) as score
FROM board
INNER JOIN pins
ON pins.board_id = board.id
INNER JOIN likes
ON pins.id = likes.pin_id
ORDER BY score
$sql = "SELECT * FROM books LEFT JOIN users
ON books.readby=users.user_id WHERE users.email IS NOT NULL";
$result = mysql_query($sql);
while($row = mysql_fetch_array($result))
{
echo $row['readby']. " - read 10 books";
} //while ends
this is the code I have so far. I am trying to retrieve the number of books read by each user
and echo the results. echo the user_id and number of books he/she read
books table is like this : id - name - pages - readby
the row readby contains the user id.any ideas/suggestions? I was thinking about using count() but Im not sure how to go about doing that.
A subquery can return the count of books read per user. That is left-joined back against the main table to retrieve the other columns about each user.
Edit The GROUP BY had been omitted...
SELECT
users.*,
usersread.numread
FROM
users
/* join all user details against count of books read */
LEFT JOIN (
/* Retrieve user_id (via readby) and count from the books table */
SELECT
readby,
COUNT(*) AS numread
FROM books
GROUP BY readby
) usersread ON users.user_id = usersread.readby
In your PHP then, you can retrieve $row['numread'] after fetching the result.
// Assuming you already executed the query above and checked errors...
while($row = mysql_fetch_array($result))
{
// don't know the contents of your users table, but assuming there's a
// users.name column I used 'name' here...
echo "{$row['name']} read {$row['numread']} books.";
}
You can use count() this way:
<?php
$count = mysql_fetch_array(mysql_query("SELECT COUNT(`user_id`) FROM books LEFT JOIN users ON books.readby=users.user_id WHERE users.email IS NOT NULL GROUP BY `user_id`"));
$count = $count[0];
?>
Hope this helps! :)
I just need help refining this script to give me the values from both tables joined on the ID.
Basically I want the ID from both tables and then be able to get the other values from both tables based on the IDs (if need be) and display them in a loop.
The code I have is below but won't work.
$select = myQ("SELECT * FROM users a WHERE EXISTS (SELECT 1 FROM `videos` b WHERE a.id = b.id GROUP BY b.id HAVING count(*) > 1) ");
$i=0;
while ($row = myF($select)) {
$resultsLoopArray[$i]["videos.id"] = $row["id"];
$resultsLoopArray[$i]["videos.vid"] = $row["vid"];
$resultsLoopArray[$i]["users.username"] = $row["username"];
$i++;
}
if (isset($resultsLoopArray)) {
$tpl->Loop("searchResultsLoop", $resultsLoopArray);
}
For now all I need is the username from the users table, the id and video id from the video table.
Can someone help by chance?
you question is bit confusing me..
As for my understanding I am posting this soultion..
If you have two tables users , videos then .
$sql = "SELECT users.username , videos.* from users, videos where users.user_id = videos.user_id";
this query will fetch all record from users and videos table where user id is present in videos tables ...