This is my mysql query, but it is not working
update jos_users set name =
(SELECT name
FROM jos_users
WHERE id = 478) where id =477
can any one please tell how to execute this query? or other possibility?
the error-message you should get is:
#1093 - You can't specify target table 'jos_users' for update in FROM clause
wich means you cant use the same table you're updating in a subselect. anywa, there's a litte workaround to avoid this: just use a nested subselect instead:
update
jos_users
set
name = (select name from
(SELECT name FROM jos_users WHERE id = 478)
AS subselect_value)
where
id = 477
Related
I have this query.
UPDATE messages
SET seen_by = CONCAT( seen_by, '3,')
WHERE id IN (SELECT id FROM messages WHERE NOT FIND_IN_SET(3, seen_by) AND chat_id = 350)
But when I try to execute it, it gives me this error
You can't specify target table 'messages' for update in FROM clause
I want to update the same table what I have used in my WHERE clause. How can I do that?
You don't even need a subquery.
Just replace WHERE id IN (SELECT id FROM messages WHERE xyz) by WHERE xyz.
This is more straight forward and doesn't have to first load all IDs into RAM (if it would even have allowed you).
I am trying to update the member row with the highest start date using:
UPDATE at_section_details a
SET a.sd_end_date = ?
, a.sd_details = ?
WHERE a.cd_id = ?
AND a.sd_start_date = (SELECT MAX(b.sd_start_date)
FROM at_section_details b
WHERE b.cd_id = ?)
The error message is:
"SQLException in updateYMGroup: java.sql.SQLException: You can't specify target table 'a' for update in FROM clause
The table structure is:
sd_id - primary key
cd_id - foreign key (many occurrences)
sd_section
sd_pack
sd_start_date
sd_end_date
sd_details
A member (cd_id) can start and then transfer out.
The member can then transfer in again (new start date). When they transfer out we want to pick up the max start date to transfer out against.
Any assistance would be greatly appreciated.
Regards,
Glyn
You should be able to use the LIMIT statement with an ORDER BY. Something along these lines:
UPDATE at_section_details a
SET a.sd_end_date=?, a.sd_details=?
WHERE a.cd_id=?
ORDER BY a.sd_start_date DESC
LIMIT 1
As it says on this post MySQL Error 1093 - Can't specify target table for update in FROM clause
In My SQL you can't have an update with the same table you are updating inside a subquery.
I would try to change your sub query to some like this
(Select x.* from (select max...) as x)
Sorry for abbreviating the code, I'm on mobile.
This query should work:
UPDATE at_section_details
JOIN (
SELECT cd_id, MAX(sd_start_date) sd_start_date
FROM at_section_details
WHERE cd_id = ?
GROUP BY cd_id
) AS t2 USING (cd_id, sd_start_date)
SET sd_end_date=?, sd_details=?;
See this SQL Fiddle for an example
You can try this mate:
UPDATE at_section_details SET sd_end_date = <input>, sd_details = <input>
WHERE cd_id IN (
SELECT cd_id FROM at_section_details
WHERE cd_id = <input>
ORDER BY sd_start_date DESC
LIMIT 1
);
I have a database with 2 tables:
"services" and "service_performance"
Those 2 tables have a SERVICE_ID column.
In "services" the SERVICE_ID values are unique (each service has a single ID/entry).
In "service_performance" there is an AVERAGE_MEMORY column with multiple entries per service_id
I am trying to update the MAX_VALUE column in "services" table with the highest AVERAGE_MEMORY value taken from the "service_performance" table.
I know my query is wrong because it throws an error:
1054 - Unknown column 'service_performance.SERVICE_ID' in 'where clause'
While 'service_performance.SERVICE_ID' does exist.
Here is my query:
update _services
set MAX_VALUE = (SELECT MAX(AVERAGE_MEMORY) AS SERVICE_ID FROM service_performance)
where exists
(select *
from services
where `services`.`SERVICE_ID` = `service_performance`.`SERVICE_ID`);
You should find that this version works in MySQL:
update services s join
(select service_id, MAX(AVERAGE_MEMORY) as maxmem
from service_performance
group by service_id
) sp
on s.service_id = sp.service_id
set s.MAX_VALUE = sp.maxmem;
Your version would work if it had the right table name in the where clauses:
update services
set MAX_VALUE = (SELECT MAX(AVERAGE_MEMORY) AS SERVICE_ID
FROM service_performance
WHERE `services`.`SERVICE_ID` = `service_performance`.`SERVICE_ID`)
where exists (select *
from service_performance
where `services`.`SERVICE_ID` = `service_performance`.`SERVICE_ID`
);
I am assuming that update _services is a typo and should really be update services.
MySQL is complaining because in this query there is no service_performance table
Try it like this:
UPDATE _services s INNER JOIN service_performance p
ON s.SERVICE_ID=p.SERVICE_ID
SET s.MAX_VALUE=MAX(p.AVERAGE_MEMORY) GROUP BY p.SERVICE_ID
I don't have a database to test on, but firstly you haven't given the subquery an alias, so it doesn't know what service_performance.Service_ID is.
Secondly, in this context the subquery needs to return a single value rather than a table, so you may not be able to reference it. If adding the alias to the subquery doesn't work, then something like the following should work:
update _services
set MAX_VALUE = (SELECT MAX(AVERAGE_MEMORY) AS SERVICE_ID FROM service_performance
INNER JOIN
services
on services.SERVICE_ID = service_performance.SERVICE_ID)
I got two MySQL working fine and i'm trying to find a way to combine them into one single query.
First, it selects ID of an employee.
SELECT 'ID' FROM `employee` ORDER BY ID DESC LIMIT 1;
Let's say it returns ID 100;
Then update data of employees whose ID is 100
UPDATE 'LOG' SET `TIME_EXIT`='2013/02/22' WHERE `ID`='100';
Can i do it all in a single query?
Just add them together:
UPDATE LOG SET TIME_EXIT = '2013/02/22'
WHERE ID = (
SELECT ID
FROM employee
ORDER BY ID DESC
LIMIT
);
But based on that code currently it'll only ever update the last employee, you will need to select the correct employee by using some other identifier to ensure you have the correct one.
UPDATE LOG SET TIME_EXIT = '2013/02/22'
WHERE ID = (
SELECT ID
FROM employee
WHERE NAME = 'JOHN SMITH'
ORDER BY ID DESC
LIMIT 1
);
It's now a few months old, but maybe helps you or others finding this via google…
If you want to UPDATE a field in the same selected table use this:
UPDATE LOG SET
TIME_EXIT = '2013/02/22'
WHERE ID = (
SELECT ID
FROM (
SELECT ID
FROM LOG
WHERE whatEverYouWantToCheck = whateverYouNeed
) AS innerResult
)
So, you SELECT id from a subselect. If you try to subselect it directly, mySQL quites with your error message You can't specify target table 'log' for update in FROM clause, but this way you hide your subsubquery in a subquery and that seems to be fine. Don't forget the AS innerResult to avoid getting the error message #1248 - Every derived table must have its own alias. Also match the subsubquery field name to the subquery field name in case you do something like SELECT COUNT(*) or SELECT CONCAT('#', ID)
I tried:
UPDATE giveaways SET winner = '1' WHERE ID = (SELECT MAX(ID) FROM giveaways)
But it gives:
#1093 - You can't specify target table 'giveaways' for update in FROM clause
This article seems relevant but I can't adapt it to my query. How can I get it to work?
Based on the information in the article you linked to this should work:
update giveaways set winner='1'
where Id = (select Id from (select max(Id) as id from giveaways) as t)
This is because your update could be cyclical... what if updating that record causes something to happen which made the WHERE condition FALSE? You know that isn't the case, but the engine doesn't. There also could be opposing locks on the table in the operation.
I would think you could do it like this (untested):
UPDATE
giveaways
SET
winner = '1'
ORDER BY
id DESC
LIMIT 1
Read more
update giveaways set winner=1
where Id = (select*from (select max(Id)from giveaways)as t)
create table GIVEAWAYS_NEW as(select*from giveaways);
update giveaways set winner=1
where Id=(select max(Id)from GIVEAWAYS_NEW);
Make use of TEMP TABLE:
as follows:
UPDATE TABLE_NAME SET TABLE_NAME.IsActive=TRUE
WHERE TABLE_NAME.Id IN (
SELECT Id
FROM TEMPDATA
);
CREATE TEMPORARY TABLE TEMPDATA
SELECT MAX(TABLE_NAME.Id) as Id
FROM TABLE_NAME
GROUP BY TABLE_NAME.IncidentId;
SELECT * FROM TEMPDATA;
DROP TABLE TEMPDATA;
You can create a view of the subquery first and update/delete selecting from the view instead..
Just remember to drop the view after.