[英语]I am about to do something
I am about to do something
我正好要做某事,我准备做某事。
I was about to leave.
我正好要离开。
I am about to do this
I am about to do something
我正好要做某事,我准备做某事。
I was about to leave.
我正好要离开。
I am about to do this
从 http://www.mongodb.org/downloads 下载 mongodb 压缩包,
解压到某个目录下,假设最后的目录路径为:c:\mongodb\,将 ;c:\mongodb\bin
追加到环境变量 path 中。
新建一个目录用来存放数据库文件,比如该目录为:c:\mongodb\data 。
命令行下执行:
mongod --dbpath c:\mongodb\data
命令行下执行:
mongo
进入数据库终端(默认是连接到 test 数据库):
> var x = "hello world" > x hello world >
复制/克隆一条查询结果,并将它插入到数据库中:
将 pk 值设为 None 即可:
blog = Blog(name='My blog', tagline='Blogging is easy') blog.save() # post.pk == 1 blog.pk = None blog.save() # post.pk == 2
如果该 model 继承于另一个 model 的话,必须将 pk
和 id
的值都设为 None:
class ThemeBlog(Blog): theme = models.CharField(max_length=200) django_blog ...
本文假设读者已经知道如何编写基本的装饰器代码,否则请自行 google:“python 装饰器”and/or “python decorator”。
from functools import wraps def object_does_not_exist(func): @wraps(func) def returned_wrapper(request, *args, **kwargs): try: return func(request, *args, **kwargs) except ObjectDoesNotExist: raise Http404() return returned_wrapper
用法:
@object_does_not_exist def detail(request): pass
第一种写法:
def object_does_not_exist(redirect=None): def decorator ...
错误详情:
# m4 /etc/mail/sendmail.mc > /etc/mail/sendmail.cf *** ERROR: FEATURE() should be before MAILER() *** MAILER(`local') must appear after FEATURE(`always_add_domain')*** ERROR: FEATURE() should be before MAILER() *** MAILER(`local') must appear after FEATURE(`allmasquerade')*** ERROR: FEATURE() should be before MAILER()
解决办法:
按照提示,编辑 /etc/mail/sendmail.mc 文件 ...
more ...