mysql usage of 'not in' without column value - mysql

Question

i have a table Transactions that looks similar to this:
id Type Field ObjectId NewValue
1 AddLink HasMember 4567 someDomain/someDirectory/1231
2 AddLink HasMember 4567 someDomain/someDirectory/1232
3 AddLink HasMember 4567 someDomain/someDirectory/1233
4 DeleteLink HasMember 4567 someDomain/someDirectory/1231
The numeric end of "NewValue" is what i am interested in.
In Detail, i need those records where i have a record where type is "AddLink" and where no newer record of type "DeleteLink" exists, i.e. the records with id = 2 or 3 (since 4 deletes 1)
The "ObjectId" as well as the numeric bit of "NewValue" both are IDs of entries of the "tickets" table, and i need the relevant tickets.
i tried this:
SELECT `Tickets`.* FROM `Transactions` AS `addedLinks`
LEFT JOIN `Tickets` ON RIGHT (`addedLinks`.`NewValue`, 4) = `Tickets`.`id`
WHERE `addedLinks`.`Type` = 'AddLink'
AND `addedLinks`.`Field` = 'Hasmember'
AND `addedLinks`.`ObjectId` = '4567'
AND NOT RIGHT (`addedLinks`.`NewValue`, 4) in (
SELECT `Tickets`.* FROM `Transactions` AS `deletedLinks`
LEFT JOIN `Tickets` ON RIGHT (`deletedLinks`.`NewValue`, 4) = `Tickets`.`id`
WHERE `deletedLinks`.`Type` = 'DeleteLink'
AND `addedLinks`.`id` < `deletedLinks`.`id`
AND `deletedLinks`.`Field` = 'Hasmember'
AND `deletedLinks`.`ObjectId` = '4567' )
This gives me:
SQL Error (1241): Operand should contain 1 column(s)
Unless i got something wrong, the problem is
RIGHT (`addedLinks`.`NewValue`, 4)
in the "AND NOT ... in()" statement.
Could anyone point me in the right direction here?
[EDIT]
Thanks to David K-J, the following works:
SELECT `Tickets`.* FROM `Transactions` AS `addedLinks`
LEFT JOIN `Tickets` ON RIGHT (`addedLinks`.`NewValue`, 4) = `Tickets`.`id`
WHERE `addedLinks`.`Type` = 'AddLink'
AND `addedLinks`.`Field` = 'Hasmember'
AND `addedLinks`.`ObjectId` = '5376'
AND NOT (RIGHT (`addedLinks`.`NewValue`, 4)) in (
SELECT `id` FROM `Transactions` AS `deletedLinks`
WHERE `deletedLinks`.`Type` = 'DeleteLink'
AND `addedLinks`.`id` < `deletedLinks`.`id`
AND `deletedLinks`.`Field` = 'Hasmember'
AND `deletedLinks`.`ObjectId` = '5376' )
but i don't understand why?

Answer 1

The problem here is your sub-select, as you are using it to provide the value of an IN clause, your sub-select should only select the id field, i.e. Transactions.* -> Transactions.id
So you end up with:
...
AND NOT (RIGHT (`addedLinks`.`NewValue`, 4)) IN
SELECT id FROM Transactions AS deletedLinks WHERE
...
The reason for this is that IN requires a list to compare with, so foo IN ( 1,2,3,4,5 ). If your subquery is selecting multiple fields, the resulting list is conceptually a list of lists (AoAs) like, [1, 'a'], [2, 'b'], [3, 'c'] and it's going to complain at you =)

Answer 2

Ah that's so complicated and with subquery... make it simpler, will be much faster
CREATE TEMPORARY TABLE `__del_max`
SELECT `NewValue`, MAX(`id`) as id FROM tickets
WHERE type = 'DeleteLink'
GROUP BY NewValue;
CREATE INDEX _nv ON __del_max(`NewValue`)
SELECT * FROM `tickets`
LEFT OUTER JOIN `__del_max` ON tickets.NewValue = __del_max.NewValue AND __del_max.id > tickets.id
WHERE __del_max.id IS NULL
You can have it in single, big join, but it'd be beneficial to have it in TMP table so you can add an index ;)