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Efficiently convert rows to columns in sql server
...nt, PostalCode, LastName, AccountNumber)
) piv;
See Demo.
Pivot with unknown number of columnnames
If you have an unknown number of columnnames that you want to transpose, then you can use dynamic SQL:
DECLARE @cols AS NVARCHAR(MAX),
@query AS NVARCHAR(MAX)
select @cols = STUFF((SELECT ',...
Understanding repr( ) function in Python
...
Can you also let us know some use cases when one should use repr function. I am unable to comprehend that
– gaurav parashar
May 17 '19 at 12:22
...
CSS last-child selector: select last-element of specific class, not last child inside of parent?
...This is actually applying the class to the LAST instance only because it's now in reversed order.
Here is a working example for you:
<!doctype html>
<head><title>CSS Test</title>
<style type="text/css">
.some-class { margin: 0; padding: 0 20px; list-style-type: square...
What's “requestCode” used for on PendingIntent?
... No, It is not necessary for different intents. And I don't know why the documentation doesn't say anything about it, but I learnt this when setting repeating alarms and also when using the same intent.
– Minhaj Arfin
Feb 3 '14 at 12:46
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How to make Git pull use rebase by default for all my repositories?
...
There are now 3 different levels of configuration for default pull behaviour. From most general to most fine grained they are:
1. pull.rebase
Setting this to true means that git pull is always equivalent to git pull --rebase (unless ...
best practice to generate random token for forgot password
...ector,
'validator' => bin2hex($token)
]);
$expires = new DateTime('NOW');
$expires->add(new DateInterval('PT01H')); // 1 hour
$stmt = $pdo->prepare("INSERT INTO account_recovery (userid, selector, token, expires) VALUES (:userid, :selector, :token, :expires);");
$stmt->execute([
...
How to apply multiple styles in WPF
...der the heading "How can I set multiple styles in WPF?"
That blog is dead now, so I'm reproducing the post here
WPF and Silverlight both offer the ability to derive a Style from another Style through the “BasedOn” property. This feature enables developers to organize their styles using a hi...
How to make an Android Spinner with initial text “Select One”?
...e from above into your project, e.g. into package com.example.customviews. Now in your layout xml, instead of <Spinner ...> use <com.example.customviews.NoDefaultSpinner ...> The rest of the code can stay the same. Don't forget to add the android:prompt attribute to the <com.example.c...
Why are dashes preferred for CSS selectors / HTML attributes?
...elopers avoided it like the plague. Of course, we don't need the backslash nowadays, but the dash-etiquette has already been firmly established.
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Standard alternative to GCC's ##__VA_ARGS__ trick?
There is a well-known problem with empty args for variadic macros in C99.
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