From 9b452a4dfb2e55b45aeceeab6e9f26155578c495 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?L=E4=B8=B6?= <37858623+chen-kay@users.noreply.github.com>
Date: Fri, 19 Mar 2021 15:02:47 +0800
Subject: [PATCH] Update schema.py

Migrations for auth fails on Django 3.1: KeyError: 'deferrable'
---
 sql_server/pyodbc/schema.py | 1 +
 1 file changed, 1 insertion(+)

diff --git a/sql_server/pyodbc/schema.py b/sql_server/pyodbc/schema.py
index b718822..6702238 100644
--- a/sql_server/pyodbc/schema.py
+++ b/sql_server/pyodbc/schema.py
@@ -68,6 +68,7 @@ class DatabaseSchemaEditor(BaseDatabaseSchemaEditor):
     sql_rename_table = "EXEC sp_rename %(old_table)s, %(new_table)s"
     sql_create_unique_null = "CREATE UNIQUE INDEX %(name)s ON %(table)s(%(columns)s) " \
                              "WHERE %(columns)s IS NOT NULL"
+    sql_create_unique = "ALTER TABLE %(table)s ADD CONSTRAINT %(name)s UNIQUE (%(columns)s)"
 
     def _alter_column_default_sql(self, model, old_field, new_field, drop=False):
         """