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Error 1022 - Can't write; duplicate key in table
...ou can not have the same foreign key names in the database tables.
Check all your tables and all your foreign keys and avoid having two foreign keys with the same exact name.
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Auto code completion on Eclipse
I want Eclipse to automatically suggest to me all possible options, while I'm writing some variable/class name or keyword, like in Flash Develop or Visual Studio.
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Pythonic way to combine FOR loop and IF statement
...>>> xyz = [0, 12, 4, 6, 242, 7, 9]
>>>
>>> known_things = sorted(set(a.iterkeys()).intersection(xyz))
>>> unknown_things = sorted(set(xyz).difference(a.iterkeys()))
>>>
>>> for thing in known_things:
... print 'I know about', a[thing]
...
I k...
Skip rows during csv import pandas
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^ No need to import at all, it is directly accessible as pd.compat.StringIO .
– cs95
Apr 8 '19 at 17:51
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Samples of Scala and Java code where Scala code looks simpler/has fewer lines?
I need some code samples (and I also really curious about them) of Scala and Java code which show that Scala code is more simple and concise then code written in Java (of course both samples should solve the same problem).
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Check if a Windows service exists and delete in PowerShell
...ee Remove-Service doc)
For example:
$service = Get-WmiObject -Class Win32_Service -Filter "Name='servicename'"
$service.delete()
Or with the sc.exe tool:
sc.exe delete ServiceName
Finally, if you do have access to PowerShell 6.0:
Remove-Service -Name ServiceName
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In STL maps, is it better to use map::insert than []?
...els natural and is clear to read whereas he preferred map.insert(std::make_pair(key, value)) .
13 Answers
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window.location.href and window.open () methods in JavaScript
...f is a property, not a method, but Internet Explorer (version 10 at least) allows you to treat href as a method too. I've seen it work, only in IE10, on one page I've used. That's probably why the asker was calling href a method. See the question IE incompatability with window.location.href. But yes...
How to list all users in a Linux group?
How do I list all members of a group in Linux (and possibly other unices)?
20 Answers
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What is the difference between lock and Mutex?
...hine.
bool firstInstance;
Mutex mutex = new Mutex(false, @"Local\DASHBOARD_MAIN_APPLICATION", out firstInstance);
if (!firstInstance)
{
//another copy of this application running
}
else
{
//run main application loop here.
}
// Refer to the mutex down here so garbage collection doesn't chu...