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Reading CSV file and storing values into an array
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LINQ way:
var lines = File.ReadAllLines("test.txt").Select(a => a.Split(';'));
var csv = from line in lines
select (from piece in line
select piece);
^^Wrong - Edit by Nick
It appears the original answerer was attempting to populate csv with a...
CSS selector for first element with class
I have a bunch of elements with a class name red , but I can't seem to select the first element with the class="red" using the following CSS rule:
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Code equivalent to the 'let' keyword in chained LINQ extension method calls
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Let doesn't have its own operation; it piggy-backs off of Select. You can see this if you use "reflector" to pull apart an existing dll.
it will be something like:
var result = names
.Select(animalName => new { nameLength = animalName.Length, animalName})
.Where...
MySQL CONCAT returns NULL if any field contain NULL
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convert the NULL values with empty string by wrapping it in COALESCE
SELECT CONCAT(COALESCE(`affiliate_name`,''),'-',COALESCE(`model`,''),'-',COALESCE(`ip`,''),'-',COALESCE(`os_type`,''),'-',COALESCE(`os_version`,'')) AS device_name
FROM devices
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How do I extract a sub-hash from a hash?
...e same:
h1 = {:a => :A, :b => :B, :c => :C, :d => :D}
h2 = h1.select {|key, value| [:b, :d, :e, :f].include?(key) } # => {:b=>:B, :d=>:D}
h1 = Hash[h1.to_a - h2.to_a] # => {:a=>:A, :c=>:C}
And if you want to patch that into the Hash class:
class Hash
def extract...
How to implement classic sorting algorithms in modern C++?
...ed and hybrid amalgamation of more elementary sorting algorithms , such as selection sort, insertion sort, quick sort, merge sort, or heap sort.
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SQL Server Installation - What is the Installation Media Folder?
... Server 2019 Developer version. Was lost with dialog prompted from step 3 "Select installation media". This Andy Leonard blog helped me: 1. Downloaded installation package from SQL Server downloads. 2. Launch downloaded wizard > Select installation type > Download media 3. Right-click on the d...
Why use the SQL Server 2008 geography data type?
...tance < 500 * 1609.344
orderby distance
select f;
return q1.FirstOrDefault();
}
Then there is a very good reason to use Geography.
Explanation of spatial within Entity Framework.
Updated with Creating High Performance Spatial Databases
As I noted on Noe...
Multiline strings in VB.NET
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I used this variant:
Dim query As String = <![CDATA[
SELECT
a.QuestionID
FROM
CR_Answers a
INNER JOIN
CR_Class c ON c.ClassID = a.ClassID
INNER JOIN
CR_Questions q ON q.QuestionID = a.QuestionID
...
Xcode 4: How do you view the console?
...nces -> Alerts and click on 'Run starts' on the left hand column.
Then select 'Show Debugger' and when you run the app the NSLog output will be displayed below the editor pane.
This way you don't have to select on the 'up arrow' button at the bottom bar.
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