Custom Django binary field & SQL Server 2008

Question

我有一个小表格：

CREATE TABLE [organization_division] (
[id] int IDENTITY (1, 1) NOT NULL PRIMARY KEY,
[uuid] binary(16) NOT NULL
)

我可以用SQL查询插入一条记录：

INSERT INTO [organization_division] ([uuid]) VALUES (0x244c71c6c9444f38b67ab1dcfbb5fc32)

这个表的Django模型是：

from apps.lib.fields import GUIDField
class Division(models.Model):
    uuid = GUIDField() 

GUIDField是我创建自定义字段的尝试：

class GUIDField(models.Field):    
    description = "GUID binary field"
    __metaclass__ = models.SubfieldBase
    def __init__(self, *args, **kwargs):
        kwargs['max_length'] = 16
        super(GUIDField, self).__init__(*args, **kwargs)
    def db_type(self, connection):
        return 'binary(16)'

我需要将16字节的二进制数据从ORM实例传递到数据库。最有可能的是，我必须在SQL Server端获得一个后跟0x的无引号字符串。。。但是怎么做呢？

我使用的是unixodbc、pyodbc、django-odbc

Answer 1

from django.db import models
import pyodbc
class GUIDField(models.Field):    
    description = "GUID binary field"
    __metaclass__ = models.SubfieldBase
    def __init__(self, *args, **kwargs):
        kwargs['max_length'] = 16
        super(GUIDField, self).__init__(*args, **kwargs)
    def db_type(self, connection):
        return 'binary(16)'
    def get_db_prep_value(self, value):
        if value is None:
            return None
        return pyodbc.BINARY(value)