Only indent if the subsequent line is a subquery

db/migrate/20170622135451_rename_duplicated_variable_key.rb

@@ -8,18 +8,18 @@ class RenameDuplicatedVariableKey < ActiveRecord::Migration
   def up
     execute(<<~SQL)
       UPDATE ci_variables
-        SET #{key} = CONCAT(#{key}, #{underscore}, id)
-        WHERE id IN (
-          SELECT *
-            FROM ( -- MySQL requires an extra layer
-              SELECT dup.id
-                FROM ci_variables dup
-                INNER JOIN (SELECT max(id) AS id, #{key}, project_id
-                              FROM ci_variables tmp
-                              GROUP BY #{key}, project_id) var
-                USING (#{key}, project_id) where dup.id <> var.id
-            ) dummy
-        )
+      SET #{key} = CONCAT(#{key}, #{underscore}, id)
+      WHERE id IN (
+        SELECT *
+        FROM ( -- MySQL requires an extra layer
+          SELECT dup.id
+          FROM ci_variables dup
+          INNER JOIN (SELECT max(id) AS id, #{key}, project_id
+                      FROM ci_variables tmp
+                      GROUP BY #{key}, project_id) var
+          USING (#{key}, project_id) where dup.id <> var.id
+        ) dummy
+      )
     SQL
   end