contactsmanager shall limit number of results early

[blizzz]

fixes#20009 cf. #20009 (comment)

Optional arguments are added to the ContactsStore API, so it should be okay to backport it to 19. Support for limiting results is implemented down the stack already. Since the contactsmenu reduces results according to sharing.maxAutocompleteResults and the search filter is passed to the backend, limiting the possible results up front does not sacrifice anything, but improves performance.

[blizzz]

/backport to stable19

[MorrisJobke]

Code looks good and makes sense 👍

[skjnldsv]

🐘

[blizzz]

/backport to stable18

[ChristophWurst]

not sacrifice anything, but improves performance.

The limit is passed down, but not the sort order. So the result correctness is only given if database sorts the same way as the PHP code does later on.

Let's say you have 100 contacts. The database sorts them by UID. You select the first 20 rows, then sort the rows by name. It's not the same result as fetching all 100 contacts, sorting them and then taking the first 20 entries.

SELECT DISTINCT `cp`.`cardid` FROM `oc_cards_properties` `cp` WHERE (`cp`.`addressbookid` = :id) AND ((`cp`.`name` = 'EMAIL') OR (`cp`.`name` = 'FN')) LIMIT 25; is the query run on the DB.

[blizzz]

You have (still) too many results 😅