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What's wrong with nullable columns in composite primary keys?
...ow in a table: when a table has a primary key, you have a guranteed way to select any row from it.
A unique constraint does not necessarily identify every row; it just specifies that if a row has values in its columns, then they must be unique. This is not sufficient to uniquely identify every row...
jQuery : eq() vs get()
... the DOM elements matched by the jQuery object.
http://api.jquery.com/eq-selector/
Description: Select the element at index n within the matched set.
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What is the equivalent of bigint in C#?
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I just had a script that returned the primary key of an insert and used a
SELECT @@identity
on my bigint primary key, and I get a cast error using long - that was why I started this search. The correct answer, at least in my case, is that the type returned by that select is NUMERIC which equates t...
Bash history without line numbers
...ply vertical whitespace or indenting at paragraph breaks, depending on the selected style."
$ history | awk ' $1=""; {print}'
clear
echo "In word processing and desktop publishing, a hard return or paragraph break indicates a new paragraph, to be distinguished from the soft return at the end of a...
Searching if value exists in a list of objects using Linq
...from customer in list
where customer.FirstName == "John"
select customer).Any();
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How to reshape data from long to wide format
...mes(df) <- unique(dat1$name)
df
sqldf package:
library(sqldf)
sqldf('SELECT name,
MAX(CASE WHEN numbers = 1 THEN value ELSE NULL END) x1,
MAX(CASE WHEN numbers = 2 THEN value ELSE NULL END) x2,
MAX(CASE WHEN numbers = 3 THEN value ELSE NULL END) x3,
MAX(CASE WHEN numbe...
Opening project in Visual Studio fails due to nuget.targets not found error
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Install Nuget.
Right click on the solution and select "Enable NuGet
Package Restore". In Visual Studio 2013 and later, select "Restore NuGet Packages" instead.
Click Ok on the warning.
Close and re-open the solution.
Should now be hunky-dory.
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Generate C# class from XML
... file as classes.
Copy your XML file's content to clipboard
In editor, select place where you want your classes to be pasted
From the menu, select EDIT > Paste Special > Paste XML As Classes
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Breakpoints are crossed out, how can I make them valid?
...akpoints' in eclipse.
When you click on 'skip all breakpoints'(which is selected), everything will become normal
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Deleting all records in a database table
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Prefer select whenever you need to use an if expression inside a block, this way you avoid having to chain the compact method to remove nil elements.
– Sebastian Palma
Jan 18 '18 at 17:18
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