Enable frozen string for lib/gitlab/*.rb

1 files changed, 7 insertions, 5 deletions

diff --git a/lib/gitlab/database.rb b/lib/gitlab/database.rb
index 42f9605f5ac..68ed53cf64a 100644
--- a/lib/gitlab/database.rb
+++ b/lib/gitlab/database.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module Gitlab
   module Database
     # The max value of INTEGER type is the same between MySQL and PostgreSQL:
@@ -99,11 +101,11 @@ module Gitlab
       order = "#{field} #{direction}"
 
       if postgresql?
-        order << ' NULLS LAST'
+        order = "#{order} NULLS LAST"
       else
         # `field IS NULL` will be `0` for non-NULL columns and `1` for NULL
         # columns. In the (default) ascending order, `0` comes first.
-        order.prepend("#{field} IS NULL, ") if direction == 'ASC'
+        order = "#{field} IS NULL, #{order}" if direction == 'ASC'
       end
 
       order
@@ -113,11 +115,11 @@ module Gitlab
       order = "#{field} #{direction}"
 
       if postgresql?
-        order << ' NULLS FIRST'
+        order = "#{order} NULLS FIRST"
       else
         # `field IS NULL` will be `0` for non-NULL columns and `1` for NULL
         # columns. In the (default) ascending order, `0` comes first.
-        order.prepend("#{field} IS NULL, ") if direction == 'DESC'
+        order = "#{field} IS NULL, #{order}" if direction == 'DESC'
       end
 
       order
@@ -184,7 +186,7 @@ module Gitlab
       EOF
 
       if return_ids
-        sql << 'RETURNING id'
+        sql = "#{sql}RETURNING id"
       end
 
       result = connection.execute(sql)