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What is the difference between single and double quotes in SQL?
...VING and also in some built-in SQL functions like CONCAT, STRPOS, POSITION etc.
When you want to use an alias that has space in between then you can use double quotes to refer to that alias.
For example
(select account_id,count(*) "count of" from orders group by 1)sub
Here is a subquery from a...
Is False == 0 and True == 1 an implementation detail or is it guaranteed by the language?
...s to strings and number values, using == or != or <, > >=, <=, etc.
You can assign an integer to a variable and then get true or false based on that variable value.
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What is the use of ObservableCollection in .net?
...ing from the list: she get's a notification on her phone (i.e. sms / email etc)!
The observable collection works just the same way. If you add or remove something to or from it: someone is notified. And when they are notified, well then they call you and you'll get a ear-full. Of course the conseque...
Generate .pem file used to set up Apple Push Notifications
...nt/ios/certificate? I find this quite useful to see the latest expiry date etc? Is this something that happens automatically?
– IonicBurger
Jun 9 '16 at 16:30
1
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How to store a command in a variable in a shell script?
.... It can't handle redirections, pipelines, for/while loops, if statements, etc
Another common use case is when running curl with multiple header fields and payload. You can always define args like below and invoke curl on the expanded array content
curlArgs=('-H' "keyheader: value" '-H' "2ndkeyheade...
isset() and empty() - what to use
...y checks if the variable is set and if it is it checks it for null, "", 0, etc
Isset just checks if is it set, it could be anything not null
With empty, the following things are considered empty:
"" (an empty string)
0 (0 as an integer)
0.0 (0 as a float)
"0" (0 as a string)
NULL
FALSE
array() (...
What is the most frequent concurrency issue you've encountered in Java? [closed]
... server mode, only when the JVM recompiles after x iterations of the loop, etc. Ouch!
– Cowan
Feb 11 '09 at 6:15
2
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Use of .apply() with 'new' operator. Is this possible?
...at behave differently when called as functions, like String, Number, Date, etc.) with an array of arguments:
function construct(constructor, args) {
function F() {
return constructor.apply(this, args);
}
F.prototype = constructor.prototype;
return new F();
}
An object crea...
Delete fork dependency of a GitHub repository
...wed it to skip the VCS detection and just import the code/commits/branches etc. This was the case when importing Github --> Github. The import might not have hung if I was coming from a different VCS? Not sure. Please also note on doing this with a second repo, I had to cancel twice for it to wor...
How do I measure request and response times at once using cURL?
...
A shortcut you can add to your .bashrc etc, based on other answers here:
function perf {
curl -o /dev/null -s -w "%{time_connect} + %{time_starttransfer} = %{time_total}\n" "$1"
}
Usage:
> perf stackoverflow.com
0.521 + 0.686 = 1.290
...