backend bundle refactor

packages/engines/mssql/sql/index.js

@@ -0,0 +1,11 @@
+const columns = require('./columns');
+const foreignKeys = require('./foreignKeys');
+const primaryKeys = require('./primaryKeys');
+const tables = require('./tables');
+
+module.exports = {
+  columns,
+  tables,
+  foreignKeys,
+  primaryKeys,
+};