Add latest changes from gitlab-org/gitlab@master

1 files changed, 17 insertions, 2 deletions

diff --git a/lib/gitlab/database/migration_helpers.rb b/lib/gitlab/database/migration_helpers.rb
index f75e943671b..82a84508959 100644
--- a/lib/gitlab/database/migration_helpers.rb
+++ b/lib/gitlab/database/migration_helpers.rb
@@ -215,7 +215,7 @@ module Gitlab
         fk_name = name || concurrent_foreign_key_name(source, column)
 
         unless foreign_key_exists?(source, name: fk_name)
-          raise "cannot find #{fk_name} on #{source} table"
+          raise missing_schema_object_message(source, "foreign key", fk_name)
         end
 
         disable_statement_timeout do
@@ -931,7 +931,10 @@ module Gitlab
       def column_for(table, name)
         name = name.to_s
 
-        columns(table).find { |column| column.name == name }
+        column = columns(table).find { |column| column.name == name }
+        raise(missing_schema_object_message(table, "column", name)) if column.nil?
+
+        column
       end
 
       # This will replace the first occurrence of a string in a column with
@@ -1166,6 +1169,18 @@ into similar problems in the future (e.g. when new tables are created).
 
       private
 
+      def missing_schema_object_message(table, type, name)
+        <<~MESSAGE
+          Could not find #{type} "#{name}" on table "#{table}" which was referenced during the migration.
+          This issue could be caused by the database schema straying from the expected state.
+
+          To resolve this issue, please verify:
+            1. all previous migrations have completed
+            2. the database objects used in this migration match the Rails definition in schema.rb or structure.sql
+
+        MESSAGE
+      end
+
       def tables_match?(target_table, foreign_key_table)
         target_table.blank? || foreign_key_table == target_table
       end