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Best way to test SQL queries [closed]
...value, and all values are consecutive:
create view cm_absolute_month as
select *, year * 12 + month as absolute_month from month_value;
Now what we have to test is inherent in our spec, namely that for any tuple (year, month), there is one and only one (absolute_month), and that (absolute_month...
How to count occurrences of a column value efficiently in SQL?
...
This should work:
SELECT age, count(age)
FROM Students
GROUP by age
If you need the id as well you could include the above as a sub query like so:
SELECT S.id, S.age, C.cnt
FROM Students S
INNER JOIN (SELECT age, count(age) a...
How do I change tab size in Vim?
...hat's what would happen should tabs be used, rather than always delete one char at a time).
To make a fully educated decision as to how to set things up, you'll need to read Vim docs on tabstop, shiftwidth, softtabstop and expandtab. The most interesting bit is found under expandtab (:help 'expandta...
Select the values of one property on all objects of an array in PowerShell
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I think you might be able to use the ExpandProperty parameter of Select-Object.
For example, to get the list of the current directory and just have the Name property displayed, one would do the following:
ls | select -Property Name
This is still returning DirectoryInfo or FileInfo obje...
How to increase font size in the Xcode editor?
...)
Go to XCode > Preferences > Fonts & Color
From the 'Theme' box select the theme you want to modify (or select the theme you want to modify and click the "+" button at the bottom of the theme list to clone it first for backup, for there is no undo option)
In the source editor box there is...
Cannot highlight all occurrences of a selected word in Eclipse
...etting the C/C++ Occurrences and C/C++ Write occurrences. But still when I select a word it won't highlight all occurrences of that specific word.
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How to use UIScrollView in Storyboard
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Here are the steps with Auto Layout that worked for me on XCode 8.2.1.
Select Size Inspector of View Controller, and change Simulated Size to Freeform with height 1000 instead of Fixed.
Rename the view of View Controller as RootView.
Drag a Scroll View as subview of RootView and rename it as Scr...
Get a list of checked checkboxes in a div using jQuery
I want to get a list of names of checkboxes that are selected in a div with certain id. How would I do that using jQuery?
8...
Rails ActiveRecord date between
...ne day. The field is part of the standard timestamps, is created_at . The selected date is coming from a date_select .
11...
Resize svg when window is resized in d3.js
...u don't have to worry about sizes any more.
Here is how I did it:
d3.select("div#chartId")
.append("div")
// Container class to make it responsive.
.classed("svg-container", true)
.append("svg")
// Responsive SVG needs these 2 attributes and no width and height attr.
....