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Why would someone use WHERE 1=1 AND in a SQL clause?
...' is replaced at runtime by an actual parameter value selected from a drop-down box. The choices in the drop-down are given by:
select distinct a from t
union all
select '*' from sysibm.sysdummy1
so that you get all possible values plus "*". If the user selects "*" from the drop down box (meani...
Group query results by month and year in postgresql
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Take a look at example E of this tutorial -> https://www.postgresqltutorial.com/postgresql-group-by/
You need to call the function on your GROUP BY instead of calling the name of the virtual attribute you created on select.
I was doing what all the answers above recom...
Detect the Internet connection is offline?
...ogle would be a good way to confirm that the internet connection itself is down, so if that information is useful to you, then it might be worth the trouble.
Sidenote: Sending a Ping could be achieved in the same way that you would make any kind of two-way ajax request, but sending a ping to google...
How to get distinct values from an array of objects in JavaScript?
...many of the performance pitfalls involved (obsolete jsperf).
Performance
https://jsperf.com/filter-vs-dictionary-more-data When I ran this dictionary was 96% faster.
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How to edit log message already committed in Subversion?
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+1 for giving the command directly :-) apache.org was down right now and I couldn't follow any given link...
– Rafa
Jan 10 '11 at 16:23
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When to use thread pool in C#? [closed]
...scheduler.
If you need to make your IO related tasks concurrently such as downloading stuff from remote servers or disk access, but need to do this say once every few minutes, then make your own threads and kill them once you're finished.
Edit: About some considerations, I use thread pools for dat...
How do I iterate over a range of numbers defined by variables in Bash?
...q involves the execution of an external command which usually slows things down. This may not matter but it becomes important if you're writing a script to handle lots of data.
– paxdiablo
Oct 4 '08 at 1:45
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Why does IE9 switch to compatibility mode on my website?
...ight after <head> (see also the answer below). When I put it further down within the <head> element, it didn't work (I still got the torn page).
– Boris van Schooten
Feb 3 '12 at 12:27
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Is there a ceiling equivalent of // operator in Python?
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You can just do upside-down floor division:
def ceildiv(a, b):
return -(-a // b)
This works because Python's division operator does floor division (unlike in C, where integer division truncates the fractional part).
This also works with Pyt...
applicationWillEnterForeground vs. applicationDidBecomeActive, applicationWillResignActive vs. appli
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Use this method to pause ongoing tasks, disable timers, and throttle down
OpenGL ES frame rates. Games should use this method to pause the game.
*/
}
- (void)applicationDidEnterBackground:(UIApplication *)application
{
/*
Use this method to release shared resources, save u...