add_signup_language_index migration

db/migrations/20200810144851_add_signup_language_index.js.js

@@ -0,0 +1,14 @@
+"use strict";
+
+
+exports.up = function(knex) {
+  return knex.schema.table("subscribers", table => {
+    table.index("signup_language", "subscribers_signup_language_idx");
+  });
+};
+
+exports.down = function(knex) {
+  return knex.schema.table("email_addresses", table => {
+    table.dropIndex("signup_language", "subscribers_signup_language_idx");
+  });
+};