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Introducing FOREIGN KEY constraint may cause cycles or multiple cascade paths - why?
I've been wrestling with this for a while and can't quite figure out what's happening. I have a Card entity which contains Sides (usually 2) - and both Cards and Sides have a Stage. I'm using EF Codefirst migrations and the migrations are failing with this error:
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What's the recommended way to extend AngularJS controllers?
I have three controllers that are quite similar. I want to have a controller which these three extend and share its functions.
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How to activate virtualenv?
I have been through search and tried various alternatives without success and spent several days on it now - driving me mad.
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How to compare 2 files fast using .NET?
...ical approaches recommend reading the binary via FileStream and comparing it byte-by-byte.
18 Answers
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How to style UITextview to like Rounded Rect text field?
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There is no implicit style that you have to choose, it involves writing a bit of code using the QuartzCore framework:
//first, you
#import <QuartzCore/QuartzCore.h>
//.....
//Here I add a UITextView in code, it will work if it's added...
How to enable MySQL Query Log?
... statement received from clients and the time that query statement has submitted?
Can I do that in phpmyadmin or NaviCat?
How do I analyse the log?
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how to use sed, awk, or gawk to print only what is matched?
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My sed (Mac OS X) didn't work with +. I tried * instead and I added p tag for printing match:
sed -n 's/^.*abc\([0-9]*\)xyz.*$/\1/p' example.txt
For matching at least one numeric character without +, I would use:
sed -n 's/^.*abc\([0-9][0-9]*\)xyz.*$/\...
Retrieve only the queried element in an object array in MongoDB collection
....color": "red"}, {_id: 0, 'shapes.$': 1});
MongoDB 3.2 Update
Starting with the 3.2 release, you can use the new $filter aggregation operator to filter an array during projection, which has the benefit of including all matches, instead of just the first one.
db.test.aggregate([
// Get just t...
How can I time a code segment for testing performance with Pythons timeit?
I've a python script which works just as it should, but I need to write the execution time. I've googled that I should use timeit but I can't seem to get it to work.
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Checking if a folder exists using a .bat file [closed]
...s and if so, for a message to be displayed and then the batch file to be exited.
2 Answers
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