diff --git a/app/controllers/gits_controller.rb b/app/controllers/gits_controller.rb
index 1965f61ba..910864812 100644
--- a/app/controllers/gits_controller.rb
+++ b/app/controllers/gits_controller.rb
@@ -32,7 +32,7 @@ class GitsController < ApplicationController
         system_user = User.find_by_login(input_username) || User.find_by_mail(input_username) || User.find_by_phone(input_username)
 
         # 如果用户名密码错误
-        if !system_user.check_password?(input_password)
+        if system_user && !system_user.check_password?(input_password)
           uid_logger_error("git start: password is wrong")
           result = false
         else
diff --git a/app/controllers/subjects_controller.rb b/app/controllers/subjects_controller.rb
index 20b28121f..46f3b4850 100644
--- a/app/controllers/subjects_controller.rb
+++ b/app/controllers/subjects_controller.rb
@@ -25,13 +25,13 @@ class SubjectsController < ApplicationController
         @subjects = Subject.find_by_sql("SELECT subjects.id, subjects.user_id, subjects.name, subjects.stages_count, subjects.repertoire_id, subjects.status,
                       subjects.shixuns_count, sum(shixuns.myshixuns_count) AS myshixun_member_count FROM subjects join stage_shixuns
                       on stage_shixuns.subject_id = subjects.id join shixuns on shixuns.id = stage_shixuns.shixun_id where
-                      subjects`.`hidden` = 0 AND `subjects`.`status` = 2 AND `subjects`.`name` like '%#{search}%'
-                      AND `subjects`.`repertoire_id` = #{select} GROUP BY subjects.id ORDER BY myshixun_member_count DESC")
+                      subjects.hidden = 0 AND subjects.status = 2 AND subjects.name like '%#{search}%'
+                      AND subjects.repertoire_id = #{select} GROUP BY subjects.id ORDER BY myshixun_member_count DESC")
       else
         @subjects = Subject.find_by_sql("SELECT subjects.id, subjects.user_id, subjects.name, subjects.stages_count, subjects.repertoire_id, subjects.status,
                       subjects.shixuns_count, sum(shixuns.myshixuns_count) AS myshixun_member_count FROM subjects join stage_shixuns
                       on stage_shixuns.subject_id = subjects.id join shixuns on shixuns.id = stage_shixuns.shixun_id where
-                      `subjects`.`hidden` = 0 AND `subjects`.`status` = 2 AND `subjects`.`name` like '%#{search}%'
+                      subjects.hidden = 0 AND subjects.status = 2 AND subjects.name like '%#{search}%'
                       GROUP BY subjects.id ORDER BY myshixun_member_count DESC")
       end
     else