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Convert Rows to columns using 'Pivot' in SQL Server
..., 212),
(105, 2, 78),
(109, 2, 97),
(105, 3, 60),
(102, 3, 123),
(101, 3, 220),
(109, 3, 87);
If your values are known, then you will hard-code the query:
select *
from
(
select store, week, xCount
from yt
) src
pivot
(
sum(xcount)
for week in ([1], [2], [3])
) pi...
Command line to remove an environment variable from the OS level configuration
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Ah! What do you suppose the rational is for that?? I always avoid admin as much as possible - UNIX/BSD/Linux upbringing. Thanks a mil for the awesome diligence. +1
– caasjj
Apr 5 '16 at 20:36
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How can I Remove .DS_Store files from a Git repository?
How can I remove those annoying Mac OS X .DS_Store files from a Git repository?
25 Answers
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How to use hex color values
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How would you handle 123ABC? The compiler is burking at it not being a digit.
– Islam Q.
Mar 2 '16 at 6:28
1
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Understanding :source option of has_one/has_many through of Rails
...'ve chosen to namespace the Dog::Breed, because we want to access Dog.find(123).breeds as a nice and convenient association.
Now, if we now want to create a has_many :dog_breeds, :through => :dogs association on Pet, we suddenly have a problem. Rails won't be able to find a :dog_breeds associati...
Converting newline formatting from Mac to Windows
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In conclusion, simply replace every occurence of \n by \r\n.
Both unix2dos and dos2unix are not by default available on Mac OSX.
Fortunately, you can simply use Perl or sed to do the job:
sed -e 's/$/\r/' inputfile > outputfile # UNIX to DOS (adding CRs)
sed -e 's/\r$//' input...
How do I create a unique constraint that also allows nulls?
...et_AllowNull
UNIQUE (TicketID, TicketUnique);
If IssueID 1 has ticket 123, the UNIQUE constraint will be on values (123, NULL). If IssueID 2 has no ticket, it will be on (NULL, 2). Some thought will show that this constraint cannot be duplicated for any row in the table, and still allows multip...
How do I deploy Node.js applications as a single executable file? [duplicate]
Supposed I have written a Node.js application, and I now would like to distribute it. Of course, I want to make it easy for the user, hence I do not want him to install Node.js, run npm install and then manually type node app.js .
...
Why is Linux called a monolithic kernel?
...ion, etc.) are a tight knit group sharing the same space. This directly opposes a microkernel.
A microkernel prefers an approach where core functionality is isolated from system services and device drivers (which are basically just system services). For instance, VFS (virtual file system) and block...
Shell脚本编程30分钟入门 - 更多技术 - 清泛网 - 专注C/C++及内核技术
...文本编辑器和一个能解释执行的脚本解释器就可以了。
OS
当前主流的操作系统都支持shell编程，本文档所述的shell编程是指Linux下的shell，讲的基本都是POSIX标准下的功能，所以，也适用于Unix及BSD（如Mac OS）。
Linux
Linux默认安...