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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...
List comprehension vs map
...y be microscopically faster in some cases (when you're NOT making a lambda for the purpose, but using the same function in map and a listcomp). List comprehensions may be faster in other cases and most (not all) pythonistas consider them more direct and clearer.
An example of the tiny speed advanta...
Android View.getDrawingCache returns null, only null
...
On a big enough view, this did not work for me. (Possibly because I have a phone with very limited memory resources). The answer below by cV2 worked fine for me.
– Simon Forsberg
Jul 23 '13 at 23:16
...
Date vs DateTime
...
I created a simple Date struct for times when you need a simple date without worrying about time portion, timezones, local vs. utc, etc.
Date today = Date.Today;
Date yesterday = Date.Today.AddDays(-1);
Date independenceDay = Date.Parse("2013-07-04");
in...
How to open every file in a folder?
...u can list all files in the current directory using os.listdir:
import os
for filename in os.listdir(os.getcwd()):
with open(os.path.join(os.cwd(), filename), 'r') as f: # open in readonly mode
# do your stuff
Glob
Or you can list only some files, depending on the file pattern using the...
How to remove a field from params[:something]
My registration form, which is a form for the Users model, takes a string value for company. However, I have just made a change such that users belongs_to companies. Therefore, I need to pass an object of Company to the Users model.
...
Random “Element is no longer attached to the DOM” StaleElementReferenceException
...lement, the element reference is no longer valid. It's close to impossible for WebDriver to make a good guess about all the cases where this might happen - so it throws up its hands and gives control to you, who as the test/app author should know exactly what may or may not happen. What you want to ...
How do I insert datetime value into a SQLite database?
...
The format you need is:
'2007-01-01 10:00:00'
i.e. yyyy-MM-dd HH:mm:ss
If possible, however, use a parameterised query as this frees you from worrying about the formatting details.
...
vector删除元素erase和通用算法remove区别 - C/C++ - 清泛网 - 专注C/C++及内核技术
...代器来删除单个或者范围的元素
iterator erase(
iterator _Where
);
iterator erase(
iterator _First,
iterator _Last
);
remove函数的定义
template<class _FwdIt, class _Ty> inline
_FwdIt remove(_FwdIt _First, _FwdIt _Last, const _Ty% _Val);
与erase不同的...
error LNK2019: 无法解析的外部符号 _GetFileVersionInfoSizeW@8，该符号在...
error LNK2019: 无法解析的外部符号 _GetFileVersionInfoSizeW@8，该符号在函数 _wmain 中被引用GetFileVersionInfoSize build时出现link2019 链接错误：#pragma comment(lib, "version")解决。GetFileVersionInfoSize build时出现link2019 链接错误：
#pragma comment(lib, "v...