I'm having difficulty understanding how to Order a query by data from another table.
The existing query is: SELECT ID FROM UserTour WHERE Live = 1 ORDER BY LastUpdated DESC
This obviously Orders by the column 'LastUpdated' in the table 'UserTour'
However, I need it to be ordered by the column 'LastUpdated' which is in another table 'ImageLinks', Where 'TypeID' = 16 (again in 'ImageLinks').
I hope that makes sense.
So it would be something like: $ids = #mysql_values('SELECT ID FROM UserTour WHERE Live = 1 ORDER BY ('Select ID FROM 'ImageLinks' Where TypeID = 16 Order by LastUpdated DESC')');
Any help would be appreciated on how to do this. Cheers
If there is no relationship between the two tables your query in your question will look like this
select id from
(
SELECT
ID
, (Select ID FROM ImageLinks Where TypeID = 16
Order by LastUpdated DESC limit 1) as order_val
FROM UserTour
WHERE Live = 1
) x
ORDER BY x.order_val
which will work but will not do not any ordering as the order_val column will have a fixed value.
If the IDs are linked 1:1 (no indication that they are, but just supposin') we could do this:
select u.id
from UserTour u inner join ImageLinks i on u.ID = i.ID
where u.Live = 1 and i.TypeID = 16
order by i.LastUpdated desc
If the above is incorrect then you will have to decide how the two tables are related and join them correspondingly.
In other words, If the tables are in no way connected, then you cannot provide an ordering of one table's data based on a column in the other.
UPDATE
select
i.LinkID
, i.LastUpdated
from UserTour u inner join ImageLinks i
on u.ID = i.LinkID
where u.Live = 1 and i.TypeID = 16
group by i.LinkID, i.LastUpdated
order by i.LastUpdated desc LIMIT 30
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 :
$sql="SELECT *
FROM addresses
LEFT JOIN users ON address_id = user_id
LEFT JOIN notes ON note_id = user_id
ORDER BY adress_id DESC
LIMIT 1";
This may work:
SELECT a.address_id, u.user_id, n.note_id
FROM addresses a
LEFT JOIN users_addresses ua ON ua.ua_address_id = a.address_id
LEFT JOIN users u ON u.user_id = ua.ua_user_id
LEFT JOIN notes n ON n.note_user_id = u.user_id
ORDER BY a.address_id DESC
LIMIT 1
Here is the query to get all data from all the tables, not sure what do you mean last records from 3 tables, I can see four tables there:
SELECT *
FROM `addresses`
LEFT JOIN `users_addresses` ON `users_addresses`.`ua_address_id` = `addresses`.`address_id`
LEFT JOIN `users` ON `users`.`user_id` = `users_addresses`.`ua_user_id`
LEFT JOIN `notes` ON `notes`.`note_user_id` = `users`.`user_id`;
I have this structure (tables) of forum
I want to select last post (row from forum_post table) from category.
SQL so far:
SELECT * FROM table_post
WHERE topic_id = (SELECT MAX(id) FROM table_topic WHERE category_id = {$id})
ORDER BY id ASC LIMIT 1
Question: How to modify this select to achieve my goal?
Assuming that "last" means the biggest id, I would suggest order by and limit:
select fp.*
from forum_post fp join
forum_topic ft
on fp.topic_id = ft.id
where ft.category_id = $id
order by fp.id desc
limit 1;
I have two tables,
TABLE 1 has many of each client and campaign and is very large
TABLE 2 has only one of each client and campaign and is small.
So I want to get the lastest(highest ID) from TABLE 1 where it matches the client and campaign in TABLE 2 and only one of each.
I have tried MAX, and playing with the order by etc, but cant get it working....
The results I get are choosing the lowest ID from TABLE 1 (I want highest)
$result2 = mysql_query("SELECT table1.client,table1.campaign,table1.id
FROM table1
LEFT OUTER JOIN
table2
ON (table2.client = table1.client)
AND (table2.campaign = table1.campaign )
WHERE (table2.enabled != 'disabled')
group by campaign asc
order by client,campaign,id asc
");
Help needed....
SELECT * FROM table1
INNER JOIN
(
SELECT MAX(table1.id) AS id FROM table1
INNER JOIN table2 ON table2.client = table1.client AND table2.campaign=table1.campaign and table2.enabled != 'disabled'
GROUP BY table1.client, table1.campaign
) AS m ON m.id = table1.id
I think that's what you're asking for. For each combination of client and campaign that exists in each table, it will give you the highest ID in table 1.
I am trying to join my users table with another table using the following query...
SELECT * FROM (`activities`)
JOIN `users` ON `users`.`id` = `activities`.`user`
WHERE `user_subdomain` = 'hi' OR user_subdomain = ''
ORDER BY `activities`.`id` desc
LIMIT 10
Is there any way to do the join so that the id of the user does not replace the id of the activity?
For example, currently if there is an activity with the id of 10 and the user 2 the id will be replaced by the id of the users table and show as 2 after I run the query.
Thanks a lot for the help!
Whenever you are joining tables, you ought to be explicit about the columns you select rather than using SELECT *, and specify column aliases for them when the same column name is used in multiple tables.
SELECT
activities.id,
activities.othercol,
/* Alias to userid */
users.id AS userid,
users.name,
users.anothercolumn
FROM (`activities`)
JOIN `users` ON `users`.`id` = `activities`.`user`
WHERE `user_subdomain` = 'hi' OR user_subdomain = ''
ORDER BY `activities`.`id` desc
LIMIT 10
Though it isn't strictly necessary to prepend the table name to each, unless the column names are the same.
SELECT
activities.id AS activityid,
othercol,
users.id AS userid,
name,
anothercolumn
I want to get the latest 5 messages in the inbox.
To get the 5 latest IDs i need to use this:
SELECT
MAX(id)
FROM
samtaler
WHERE
brukerid_mottaker = 1
GROUP BY brukerid_avsender
ORDER BY id DESC
LIMIT 5
This return the correct ID's I need. But in the same query i want to select data from the same table, the row that got the id that returned from this query above.
I have tried out some things, variables and self-join but no luck:
select
p2.title,
p2.message,
#a:=max(p1.id)
from
samtaler p1
join samtaler p2
on (#a = p2.id)
where
p2.brukerid_mottaker = 1
group by p2.brukerid_avsender
order by p2.id DESC
limit 5
Why isnt this working?
This is the current data in the database:
I want to return in this case, row 13 and 4. Sorry for bad english.
Join against a subquery, instead of a plain self join. An IN() clause won't work since LIMIT cannot be used inside an IN(). It should work in the joined subquery though:
SELECT
p1.title,
p1.message,
p2.id
FROM
samtaler p1
JOIN (
SELECT MAX(id) AS id
FROM
samtaler
WHERE
brukerid_mottaker = 1
GROUP BY brukerid_avsender
ORDER BY id DESC
LIMIT 5
) p2 ON p1.id = p2.id
By this method, there is no need for variables.