1 files changed, 38 insertions, 0 deletions
diff --git a/db/migrate/20170622135451_rename_duplicated_variable_key.rb b/db/migrate/20170622135451_rename_duplicated_variable_key.rb
new file mode 100644
index 00000000000..368718ab0ce
--- /dev/null
+++ b/db/migrate/20170622135451_rename_duplicated_variable_key.rb
@@ -0,0 +1,38 @@
+class RenameDuplicatedVariableKey < ActiveRecord::Migration
+  include Gitlab::Database::MigrationHelpers
+
+  DOWNTIME = false
+
+  disable_ddl_transaction!
+
+  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
+      )
+    SQL
+  end
+
+  def down
+    # noop
+  end
+
+  def key
+    # key needs to be quoted in MySQL
+    quote_column_name('key')
+  end
+
+  def underscore
+    quote('_')
+  end
+end