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Convert Rows to columns using 'Pivot' in SQL Server
...) src
pivot
(
sum(xcount)
for week in ([1], [2], [3])
) piv;
See SQL Demo
Then if you need to generate the week number dynamically, your code will be:
DECLARE @cols AS NVARCHAR(MAX),
@query AS NVARCHAR(MAX)
select @cols = STUFF((SELECT ',' + QUOTENAME(Week)
from yt...
Average of 3 long integers
...
You can calculate the mean of numbers based on the differences between the numbers rather than using the sum.
Let's say x is the max, y is the median, z is the min (as you have). We will call them max, median and min.
Conditional checker added as per @UlugbekU...
How can I redirect HTTP requests made from an iPad?
...pphire.local.
The web app I am testing is at hosted on the dev machine at demo.cms.dev (I am using POW).
To setup the proxy, I added the following section to httpd.conf.
<VirtualHost *:80>
ServerName sapphire.local
ProxyPass / http://demo.cms.dev/
ProxyPassReverse / http://demo.cms.de...
What's the difference between deque and list STL containers?
...ue because list needed more calls to new/delete. That will obviously vary based on which STL implementation you have.
– Andy Krouwel
Jun 15 '17 at 7:22
...
Installing Python 3 on RHEL
...ded a comment for that. It's the best I found. If you want to stick to RPM-based installation, you should use IUS repositories for CentOS 7. They provide a python34u-pip.
– Samuel Phan
Oct 1 '15 at 21:11
...
Can't find the PostgreSQL client library (libpq)
...
$ sudo su
$ env ARCHFLAGS="-arch x86_64" gem install pg
Building native extensions. This could take a while...
Successfully installed pg-0.11.0
1 gem installed
Installing ri documentation for pg-0.11.0...
Installing RDoc documentation for pg-0.11.0...
WORKED...
How can I split a string into segments of n characters?
...unctions, you can ignore these.
function textToBin(text) { return textToBase(text, 2, 8); }
function textToHex(t, w) { return pad(textToBase(t,16,2), roundUp(t.length, w)*2, '00'); }
function pad(val, len, chr) { return (repeat(chr, len) + val).slice(-len); }
function print(text) { docum...
Cartesian product of multiple arrays in JavaScript
... JavaScript Style Guide - validated using ESLint with eslint-config-airbnb-base:
const f = (a, b) => [].concat(...a.map(d => b.map(e => [].concat(d, e))));
const cartesian = (a, b, ...c) => (b ? cartesian(f(a, b), ...c) : a);
Special thanks to ZuBB for letting me know about linter probl...
How to tell if JRE or JDK is installed
...uires parsing the output (e.g. 2>&1 |grep -v "Unable") which varies based on locale.
Note, Java may also exist in /Library/Internet Plug-Ins/JavaAppletPlugin.plugin/Contents/Home/bin, but at time of writing this, I'm unaware of a JRE that installs there which contains javac as well.
...
What are the GCC default include directories?
... for help, clarification, or responding to other answers.Making statements based on opinion; back them up with references or personal experience.To learn more, see our tips on writing great answers.
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