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Count, size, length…too many choices in Ruby?
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In the case where you don't provide a parameter to count it has basically the same effect as calling length. There can be a performance difference though.
We can see from the source code for Array that they do almost exactly the same thing. Here is the C code for the implementation of array.l...
What to do with branch after merge
...he merge, it's safe to delete the branch:
git branch -d branch1
Additionally, git will warn you (and refuse to delete the branch) if it thinks you didn't fully merge it yet. If you forcefully delete a branch (with git branch -D) which is not completely merged yet, you have to do some tricks to ge...
In MySQL queries, why use join instead of where?
...le about using strict typing whenever possible. Explicit is almost universally better.
Conclusion
Short of familiarity and/or comfort, I don't see any benefit to continuing to use the ANSI-89 WHERE clause instead of the ANSI-92 JOIN syntax. Some might complain that ANSI-92 syntax is more verb...
How do I escape reserved words used as column names? MySQL/Create Table
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IMHO you should quote all field names and table names always.
– rjmunro
Sep 17 '13 at 11:50
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How do I embed a single file from a GitHub gist with the new gist interface?
...tHub Gist interface has one embed snippet for the entire gist which embeds all files in the gist. The old interface had embed code for each file in the gist. Anyone know if there's a trick to embed a single file?
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pinpointing “conditional jump or move depends on uninitialized value(s)” valgrind message
... use of uninitialised data in a way that might affect your program's externally-visible behaviour.
From the Valgrind FAQ:
As for eager reporting of copies of uninitialised memory values, this has been suggested multiple times. Unfortunately, almost all programs legitimately copy uninitialised ...
Android Fragments: When to use hide/show or add/remove/replace?
...n detached from the window so it's no longer visible. So you could technically still interact with the fragment and reattach its UI later you need to. If you replace the fragment, the you are actually pulling it out of the container and it will go through all of the teardown events in the lifecycl...
廉价共享存储解决方案1-drbd+ha+nfs - 更多技术 - 清泛网 - 专注C/C++及内核技术
...缓存的情况下可能会报目录不存在的错误，无视
yum clean all
yum makecache
3安装drbd(share1和2上操作)
3.1 准备编译环境
yum -y install gcc make automake autoconf flex rpm-build kernel-devel
3.2 上传解压源文件
利用xftp 把 drbd-8.4.6.tar.gz，d...
How to clear the interpreter console?
Like most Python developers, I typically keep a console window open with the Python interpreter running to test commands, dir() stuff, help() stuff , etc.
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Split views.py in several files
...__.py use *, like this:
from viewsa import *
from viewsb import *
I actually don't know about speed issues (but I doubt there are any).
For Models it might be a bit difficult.
share
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