我有一个has_many朋友的用户模型。我希望能够通过名字找到用户的所有朋友。通过名称找到关联
我希望能够在用户名中找到所有使用字符串“john”的用户。
用户
id | email | created_at | updated_at | password_digest | remember_token | admin | username | password_reset_token | password_reset_sent_at | provider | uid | generated_password
-------+---------------------------+----------------------------+----------------------------+--------------------------------------------------------------+------------------------+-------+---------------+----------------------+------------------------+----------+-----+--------------------
27288 | ******@hotmail.com | 2014-02-19 17:25:22.545866 | 2014-02-19 17:25:22.545866 | $2a$10$hjdAPWYTorCN7NW6QawmtOMqTk.DP8m2e.I9XjfujRG8em8eq6z9G | dxowM5tTTalNLWSO_5j8sw | f | huntingtonl93 | | | | | f
23 | *******@gmail.com | 2013-07-05 17:18:59.64622 | 2013-07-05 17:18:59.64622 | $2a$10$4D0cML22vnVYuT0tJTJwMO/T4xuiGYUU70BnK1ug3K.TE1.pWG64e | FS2aVM57bX0ZiMBNuWnxLA | f | one | | | | | f
31 | ********@gmail.com | 2013-09-06 21:47:52.869246 | 2013-09-06 21:47:52.869246 | $2a$10$XW6jPGZTiYo6KZm4WWOBye0b.mpNuKGt89gMLVRCjF7kjuhzHXzJG | TUsweMN36i_eouveEFU9cQ | f | drebenok | | | | | f
6388 | *******@startupv8.com | 2013-11-25 00:20:44.124276 | 2013-11-25 00:20:44.124276 | $2a$10$O5V/8C2vs.CpkYDDwByjiOOVkf0FlWb8lsMVX/r8cPnHbL8G0gRda | 2duwh0WURFI10I1PcBnD9Q | f | ihab
朋友
id | user_id | user_id_friend | created_at | updated_at
----+---------+----------------+----------------------------+----------------------------
10 | 15 | 23 | 2013-08-13 01:55:41.406368 | 2013-08-13 01:55:41.406368
12 | 15 | 28 | 2013-08-13 01:55:57.025223 | 2013-08-13 01:55:57.025223
14 | 16 | 23 | 2013-08-13 01:57:35.910647 | 2013-08-13 01:57:35.910647
16 | 17 | 23 | 2013-08-13 01:58:01.051038 | 2013-08-13 01:58:01.051038
18 | 17 | 24 | 2013-08-13 01:58:08.866769 | 2013-08-13 01:58:08.866769