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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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How can I use if/else in a dictionary comprehension?
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@Marcin's answer covers it all, but just in case someone wants to see an actual example, I add two below:
Let's say you have the following dictionary of sets
d = {'key1': {'a', 'b', 'c'}, 'key2': {'foo', 'bar'}, 'key3': {'so', 'sad'}}
and you want ...
How to run a python script from IDLE interactive shell?
...s.call(['python', 'helloworld.py']) # Just run the program
subprocess.check_output(['python', 'helloworld.py']) # Also gets you the stdout
With arguments:
subprocess.call(['python', 'helloworld.py', 'arg'])
Read the docs for details :-)
Tested with this basic helloworld.py:
import sys
if le...
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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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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How to ignore deprecation warnings in Python
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This doesn't work for me at all, still seeing deprecationwarnings.
– user1244215
Oct 22 '13 at 0:43
9
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How to use a servlet filter in Java to change an incoming servlet request url?
... a check in the code if the URL needs to be changed and if not, then just call FilterChain#doFilter(), else it will call itself in an infinite loop.
Alternatively you can also just use an existing 3rd party API to do all the work for you, such as Tuckey's UrlRewriteFilter which can be configured th...
How to select multiple files with ?
...ltiple="multiple"
and if you are using php then you will get the data in $_FILES and
use var_dump($_FILES) and see output and do processing
Now you can iterate over and do the rest
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What does static_assert do, and what would you use it for?
...fined (as one would expect in a C++ library).
Contrast with having to actually compile SomeLibrary and your code, link everything, and run the executable only then to find out that you spent 30 minutes compiling an incompatible version of SomeLibrary.
@Arak, in response to your comment: yes, you ...
Disable cache for some images
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Please note: You do not actually prevent the browser from caching the image, you only prevent looking at the cached image. Applying proper headers to your image is the best way imho (see the solution of lhunath below). Since this way you also fill the c...