perf(sharing): Don't hit the "parent" path when we load all shares an…

[nickvergessen]

…yway

• Since fix(files_sharing): Fix getting shares by path #16988 the query did not use an index anymore when entering from getSharedWith() which does not have a path. It used to have $allRoomShares = true set, but now is using the else branch which chunks and does a query on parent in blocks of 1k

Before

MariaDB [oc]> EXPLAIN SELECT `parent`, `permissions`, `file_target` FROM `oc_share` WHERE (`share_type` = '11') AND (`share_with` = 'joas');
+------+-------------+----------+-------------+---------------------------------------------------------------+----------------------------------+-----------+------+-------+----------------------------------------------------------------+
| id   | select_type | table    | type        | possible_keys                                                 | key                              | key_len   | ref  | rows  | Extra                                                          |
+------+-------------+----------+-------------+---------------------------------------------------------------+----------------------------------+-----------+------+-------+----------------------------------------------------------------+
|    1 | SIMPLE      | oc_share | index_merge | share_with_index,share_type_with,share_with_file_target_index | share_with_index,share_type_with | 1023,1025 | NULL | 17445 | Using intersect(share_with_index,share_type_with); Using where |
+------+-------------+----------+-------------+---------------------------------------------------------------+----------------------------------+-----------+------+-------+----------------------------------------------------------------+
1 row in set (0.000 sec)

After

+------+--------------+-------------+------+--------------------------------------------------------------------------------------------------+--------------+---------+--------------+------+------------------------------------+
| id   | select_type  | table       | type | possible_keys                                                                                    | key          | key_len | ref          | rows | Extra                              |
+------+--------------+-------------+------+--------------------------------------------------------------------------------------------------+--------------+---------+--------------+------+------------------------------------+
|    1 | PRIMARY      | <subquery2> | ALL  | distinct_key                                                                                     | NULL         | NULL    | NULL         | 1000 |                                    |
|    1 | PRIMARY      | oc_share    | ref  | item_share_type_index,share_with_index,parent_index,share_type_with,share_with_file_target_index | parent_index | 9       | tvc_0._col_1 | 10   | Using index condition; Using where |
|    2 | MATERIALIZED | <derived3>  | ALL  | NULL                                                                                             | NULL         | NULL    | NULL         | 1000 |                                    |
|    3 | DERIVED      | NULL        | NULL | NULL                                                                                             | NULL         | NULL    | NULL         | NULL | No tables used                     |
+------+--------------+-------------+------+--------------------------------------------------------------------------------------------------+--------------+---------+--------------+------+------------------------------------+
4 rows in set (0.001 sec)

[artonge]

This was always true before: https://github.com/nextcloud/spreed/pull/16988/changes

Suggested change

	$shares = $this->resolveSharesForRecipient($shares, $userId, $path, $forChildren, $path === null);
	$shares = $this->resolveSharesForRecipient($shares, $userId, $path, $forChildren, true);

[artonge]

/backport to stable33