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MySQL get the date n days ago as a timestamp
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DATE_SUB will do part of it depending on what you want
mysql> SELECT DATE_SUB(NOW(), INTERVAL 30 day);
2009-06-07 21:55:09
mysql> SELECT TIMESTAMP(DATE_SUB(NOW(), INTERVAL 30 day));
2009-06-07 21:55:09
mysql> SELECT U...
How to efficiently compare two unordered lists (not sets) in Python?
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For short lists, big-O analysis is usually irrelevant because the timings are dominated by constant factors. For the longer lists, I suspect something is wrong with your benchmarking. For 100 ints with 5 repeats each, I get: 127 usec for sorted and 42 for Count...
Is there a way to 'uniq' by column?
...o you need the ,1 in -k1,1? why not just -k1?
– hello_there_andy
Nov 24 '14 at 20:10
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@hello_th...
How do you read a file into a list in Python? [duplicate]
...each line might have. When the with ends, the file will be closed automatically for you. This is true even if an exception is raised inside of it.
2. use of list comprehension
This could be considered inefficient as the file descriptor might not be closed immediately. Could be a potential issue wh...
Input text dialog Android
...et it as the view of the AlertDialog. You can customize the type of input allowed using setInputType, if you need.
If you're able to use a member variable, you can simply set the variable to the value of the EditText, and it will persist after the dialog has dismissed. If you can't use a member v...
Is there a way to instantiate objects from a string holding their class name?
...initializing or assigning to it. Have a look at its documentation here. Finally, the use of a raw function pointer is also a bit oldish. Modern C++ code should be decoupled from specific functions / types. You may want to look into Boost.Function to look for a better way. It would look like this the...
ASP.NET MVC Razor Concatenation
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You should wrap the inner part of the call with ( ):
<li id="item_@(item.TheItemId)">
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各编程语言读写文件汇总 - C/C++ - 清泛网 - 专注C/C++及内核技术
各编程语言读写文件汇总all_programming_language_file_read_write_summary读写文件本来是非常基础的代码，但工作学习中难免会有遗忘，有时又难以翻看自己写过的代码，网上搜索更是五花八门让人头大，鉴于此，清泛网 读写文件本来是...
Initializing a struct to 0
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The first is easiest(involves less typing), and it is guaranteed to work, all members will be set to 0[Ref 1].
The second is more readable.
The choice depends on user preference or the one which your coding standard mandates.
[Ref 1] Reference C99 Standard 6.7.8.21:
If there are fewe...
NSInvocation for Dummies?
...oncept of messages is central to the objective-c philosophy. Any time you call a method, or access a variable of some object, you are sending it a message. NSInvocation comes in handy when you want to send a message to an object at a different point in time, or send the same message several times. N...