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Create unique constraint with null columns
...or may not be useful. In extreme situations it might even help to maintain all three indexes (the two partial ones and a total on top).
Aside: I advise not to use mixed case identifiers in PostgreSQL.
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OS detecting makefile
... still use solely uname, but you have to deal with if/else blocks to check all MinGW, Cygwin, etc. variations.
The environment variable OS is always set to "Windows_NT" on different Windows versions (see %OS% environment variable on Wikipedia).
An alternative of OS is the environment variable MSVC (...
Can I set max_retries for requests.request?
..., predating the release of requests 1.2.1:
The requests library doesn't really make this configurable, nor does it intend to (see this pull request). Currently (requests 1.1), the retries count is set to 0. If you really want to set it to a higher value, you'll have to set this globally:
import re...
How do you test functions and closures for equality?
...s Lattner wrote on the developer forums:
This is a feature we intentionally do not want to support. There are
a variety of things that will cause pointer equality of functions (in
the swift type system sense, which includes several kinds of closures)
to fail or change depending on optimiz...
实战低成本服务器搭建千万级数据采集系统 - 更多技术 - 清泛网 - 专注C/C++...
...器。到了机器后再按照天或者半天分表，比如表名为 weibo_2013020101 、weibo_2013020112。weibo_2013020101表示2月1日上午一个表，weibo_2013020112表示2月1日下午一个表。光这样分了还是不够，1000w/2=500w，经不起压力扩展。我们还需要把表再...
Getting the name of a variable as a string
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OK, finally got it! Installed using the following pip3 install python-varname==0.1.5; imported using from varname import nameof
– enter_display_name_here
Jun 6 at 2:42
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What are all possible pos tags of NLTK?
How do I find a list with all possible pos tags used by the Natural Language Toolkit (nltk)?
8 Answers
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Cross-Domain Cookies
...erver side you need to have the following headers:
header("Access-Control-Allow-Origin: http://origin.domain:port");
header("Access-Control-Allow-Credentials: true");
header("Access-Control-Allow-Methods: GET, POST");
header("Access-Control-Allow-Headers: Content-Type, *");
Within the PHP-file yo...
How to get the sizes of the tables of a MySQL database?
I can run this query to get the sizes of all tables in a MySQL database:
16 Answers
16...
How to check if object (variable) is defined in R?
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heh. Happens to me all the time when I am testing out examples before posting, Gavin or Josh have already answered it.
– Maiasaura
Feb 20 '12 at 22:17
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