I am running an SQL statement:
$sql = "SELECT pic, userid
FROM user_details
INNER JOIN wp_users ON user_details.userid
WHERE wp_users.id = user_details.userid
LIMIT $recordstart, $pagesize
";
The query is meant to select records from user_details and wp_users, but should only select if there is a match (wp_users.id = user_details.userid).
The target is for it to basically select from a table while retrieving a record (based on the id match) from the other table
The problem is that it shows duplicate records. How can I fix this problem?
You should put your JOIN condition after ON. Like this:
$sql="select pic, userid
from user_details
inner join wp_users on (wp_users.id=user_details.userid)
limit $recordstart, $pagesize";
But the real problem is that you have more then 1 record in user_details for each corresponding record in wp_users (or vise versa).
INNER JOIN is causing database to make a Cartesian product of user_details and wp_users records. Then result table is filtered by your current WHERE condition (wp_users.id=user_details.userid). Depends on your needs you can use GROUP BY or DISTINCT if you want to retrieve unique records only.
For example, if you need userid to be unique:
$sql="select pic, userid
from user_details
inner join wp_users on (wp_users.id=user_details.userid)
group by userid
limit $recordstart, $pagesize";
SELECT DISTINCT pic, userid
FROM user_details
INNER JOIN wp_users ON wp_users.id=user_details.userid
LIMIT $recordstart, $pagesize
Use DISTINCT to return only unique rows and complete your join condition in the ON section:
$sql="select distinct pic, userid
from user_details
inner join wp_users on wp_users.id=user_details.userid
limit $recordstart, $pagesize";
use GROUP BY , because it shows duplicate records if there is multiple records in second table per on one record in first table
You left out the = part of the ON by accident.
$sql="select pic, userid
from user_details
inner join wp_users on user_details.userid
= wp_users.id
where wp_users.id=user_details.userid
limit $recordstart, $pagesize";
I might try
$sql = "select pic, userid
from user_details
inner join wp_users on user_details.userid = wp_users.id
limit $recordstart, $pagesize";
Related
My tables
$sql="SELECT *
FROM addresses
LEFT JOIN users ON address_id = user_id
LEFT JOIN notes ON note_id = user_id
ORDER BY id DESC
LIMIT 1";
This is my SQL query, my task is to show the last records from 3 tables, but the table is blank, I don't know why,thanks in advance people :)
I guess the problem is coming from the ORDER BY id DESC .
Indeed, you have no column so called id.
You should probably remove this clause, in order to make your code work.
If you want to take the last records anyway, you can put an ORDER BY address_id DESC which will do the job !
The code directly edited :
$sql="SELECT *
FROM addresses
LEFT JOIN users ON address_id = user_id
LEFT JOIN notes ON note_id = user_id
ORDER BY adress_id DESC
LIMIT 1";
This may work:
SELECT a.address_id, u.user_id, n.note_id
FROM addresses a
LEFT JOIN users_addresses ua ON ua.ua_address_id = a.address_id
LEFT JOIN users u ON u.user_id = ua.ua_user_id
LEFT JOIN notes n ON n.note_user_id = u.user_id
ORDER BY a.address_id DESC
LIMIT 1
Here is the query to get all data from all the tables, not sure what do you mean last records from 3 tables, I can see four tables there:
SELECT *
FROM `addresses`
LEFT JOIN `users_addresses` ON `users_addresses`.`ua_address_id` = `addresses`.`address_id`
LEFT JOIN `users` ON `users`.`user_id` = `users_addresses`.`ua_user_id`
LEFT JOIN `notes` ON `notes`.`note_user_id` = `users`.`user_id`;
Here is database table:
$sql[2] = "SELECT u.* , oi.* , COUNT(oi.user_id) AS count
FROM users u, order_items oi
WHERE u.id=oi.user_id ";
$result3= mysqli_query($conn,$sql[2]) or die(mysqli_error());
if (mysqli_num_rows($result3) > 0) {
while ($record = mysqli_fetch_array($result3)) {
echo $record['count'];
}
}
I want to count how much order have every user. Example: Like Thomas have 3 order, but my code is writing 4, i want to write Thomas (3), Gracian(1). Any idea how to fix it ?
Use this query:
SELECT u.id,
COUNT(oi.user_id) AS orderCount
FROM users u
LEFT JOIN order_items oi
ON u.id = oi.user_id
GROUP BY u.id
The reason we count user_id from the order_items table is because of the edge case where a given user has no orders. In this case, we want to make sure that his count would appear as zero. The COUNT function ignores NULLs, which is what we want.
There is another way to perform the sql query using subqueries:
SELECT id,
email,
address,
name,
(SELECT count(user_id) FROM order_items WHERE user_id = users.id) AS orderCount FROM users;
i am fetching records from two tables with inner join, but i am not getting proper result.
Here is my code :
real_query = "SELECT DISTINCT user.id AS uid, user.name AS unm, user.profile_pic AS upic, user_message.message_by_id AS message_by_id
FROM user INNER JOIN
user_message
ON user.id = user_message.message_by_id
where (user_message.message_to_id = '".$sess."' AND
user_message.receiver_deleted = 'No')
group by user_message.id, user_message.sent_on
order by user_message.id DESC ";
The problem is, i want to echo those user names from user table, order by user_message.id but i am not getting the result as i want.
My database has 3 tables i wish to access in the select query but I cannot seem to get it to work. Selecting from 2 tables works fine so I know everything else is working apart from my code for selecting from 3 tables. My database has been created on PHPmyadmin
The Tables are as follows:
forum_replies
reply_id
topic_id
user_id
reply_text
reply date
forum_topics
topic_id
category_id
user_id
topic_title
topic_description
topic_date
users
user_id
username
This is the code I have tried to use and shows the fields I wish to select:
$queryreply = "SELECT forum_replies.reply_id, forum_replies.topic_id, forum_replies.user_id,
forum_replies.reply_text, forum_replies.reply_date, users.user_id, users.username
forum_topics.topic_id,forum_topics.topic_title, forum_topics.topic_date
FROM forum_replies
JOIN forum_topics
ON forum_replies.topic_id = forum_topics.topic_id
JOIN users
ON forum_replies.user_id = users.user_id
";
$result = mysql_query($queryreply) or die (mysql_error());
$row = mysql_fetch_array($result);
Example in code would be appreciated. Thanks
Use this query:
SELECT a.reply_text, a.reply_date, b.topic_title, c.username
FROM forum_replies a
LEFT JOIN forum_topics b ON a.topic_id=b.topic_id
LEFT JOIN users c ON a.user_id=c.user_id
// apply WHERE, ORDER, GROUP if needed
Apart from syntax errors, you should use LEFT JOIN and table alias in your case.
To show also the topic creator's username, you can adjust the query to the following:
SELECT a.reply_text, a.reply_date, b.topic_title, c.username AS reply_user, (SELECT username FROM users WHERE user_id=b.user_id) AS topic_creator
FROM forum_replies a
LEFT JOIN forum_topics b ON a.topic_id=b.topic_id
LEFT JOIN users c ON a.user_id=c.user_id
// apply WHERE, ORDER, GROUP if needed
You miss the , after users.username..
SELECT forum_replies.reply_id, forum_replies.topic_id, forum_replies.user_id,
forum_replies.reply_text, forum_replies.reply_date, users.user_id, users.username,
forum_topics.topic_id,forum_topics.topic_title, forum_topics.topic_date
i need help getting data from different tables and insert into other different table Here are the Queries
"SELECT commentID, date, comment, subject, parentID, aBUserID FROM comments WHERE status = 'APPROVED'"
"SELECT topicID, subForumID, aBUserID, lastPostID, views, replies, startDate FROM topic WHERE status = 'APPROVED' AND topicID = $parentid";
// $parentID need to be matched from above query parentID,
"SELECT userName FROM users WHERE aBUserID = $cmtaBUserID";
// $cmtaBUserID = aBUserID from first query
"SELECT userName FROM users WHERE aBUserID = $topicaBUserID";
//$topicaBUserID = aBUserID from second query
Last 2 queries are from same table but using different where clause
i used different inner join left join from solutions posted here but non of these worked for me stuck since last 2 weeks please help
PS data from all above Queries will be inserted to a single table i need these to be combined so i can have them all in one place
If you want to perform the operation in same query use 'OR'
"SELECT userName FROM users WHERE aBUserID = $cmtaBUserID OR aBUserID = $topicaBUserID";
Please try this
SELECT userName from users where aBUserID IN(SELECT aBUserID FROM comments WHERE status = 'APPROVED')
Couldn't test it but Maybe this is what you are looking for.
SELECT c.commentID, c.date, c.comment, c.subject, c.parentID, c.aBUserID,
t.topicID, t.subForumID, t.aBUserID, t.lastPostID, t.views, t.replies, t.startDate,
u.userName
FROM
comments c
left outer join topic t on t.topicID = c.parentID
left outer join users u on u.aBUserID = c.aBUserID and u.aBUserID = t.aBUserID
WHERE
c.status = 'APPROVED' and t.status = 'APPROVED';
try this:
SELECT
comment.[commentID],
comment.[date],
comment.[comment],
comment.[subject],
comment.[parentID],
comment.[aBUserID],
commentuser.[userName],
topic.[topicID],
topic.[subForumID],
topic.[aBUserID],
topic.[lastPostID],
topic.[views],
topic.[replies],
topic.[startDate],
topic.[userName]
FROM comments comment
LEFT OUTER JOIN users commentuser
ON commentuser.aBUserID = comment.[aBUserID]
LEFT OUTER JOIN
(
SELECT
t.[topicID],
t.[subForumID],
t.[aBUserID],
t.[lastPostID],
t.[views],
t.[replies],
t.[startDate],
u2.[userName] --user from users table joined to topics table
FROM topic t
LEFT OUTER JOIN users u
ON u.aBUserID = t.[aBUserID]
WHERE t.[status] = 'APPROVED'
) topic
ON topic.topicID = comment.parentID
WHERE comment.[status] = 'APPROVED'