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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 ',...
When does invoking a member function on a null instance result in undefined behavior?
...d a weak "use a dereferenced null pointer, get undefined behavior" view.
Now we consider the question.
Yes, (a) results in undefined behavior. In fact, if this is null then regardless of the contents of the function the result is undefined.
This follows from §5.2.5/3:
If E1 has the type ...
How do I replace NA values with zeros in an R dataframe?
...u post it and not worked. Because this I posted the question. But I tried know and worked perfectly. I think I was doing something wrong.
– Renato Dinhani
Nov 17 '11 at 14:08
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What Does 'Then' Really Mean in CasperJS
...ch for explaining this. This behavior has been killing me for over a year now as my Casper functional tests for an Ajax-heavy application fail randomly all the time.
– brettjonesdev
Apr 2 '15 at 23:29
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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...
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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How to make Git pull use rebase by default for all my repositories?
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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 ...
Debug a java application without starting the JVM with debug arguments
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+1 VisualVM looks really interesting. BTW: Link is fixed now.
– sleske
Mar 15 '10 at 22:54
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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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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([
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