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How to implement one-to-one, one-to-many and many-to-many relationships while designing tables?
...ss_id, student_id # the junction table
Example queries:
-- Getting all students for a class:
SELECT s.student_id, last_name
FROM student_classes sc
INNER JOIN students s ON s.student_id = sc.student_id
WHERE sc.class_id = X
-- Getting all classes for a student:
SELEC...
Android Studio: Module won't show up in “Edit Configuration”
...or me just clicking the "Sync Project with Gradle Files" fixed it. I was really worried I had busted things beyond repair.
– startoftext
Aug 17 '15 at 6:13
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pip installing in global site-packages instead of virtualenv
Using pip3 to install a package in a virtualenv causes the package to be installed in the global site-packages folder instead of the one in the virtualenv folder. Here's how I set up Python3 and virtualenv on OS X Mavericks (10.9.1):
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Select by partial string from a pandas DataFrame
...egex search is not required, so specify regex=False to disable it.
#select all rows containing "foo"
df1[df1['col'].str.contains('foo', regex=False)]
# same as df1[df1['col'].str.contains('foo')] but faster.
col
0 foo
1 foobar
Performance wise, regex search is slower than substring s...
Static method behavior in multi-threaded environment in java
...that bother me and make several arguments in my mind.
I want to throw out all the doubts about below questions.
2 Answers
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How to generate and validate a software license key?
...g a product (developed in C#) that'll be available for downloading and installing for free but in a very limited version. To get access to all the features the user has to pay a license fee and receive a key. That key will then be entered into the application to "unlock" the full version.
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jQuery - Get Width of Element when Not Visible (Display: None)
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@Tim Banks very nice! I actually wrote a similar extension. What i've been noticing is very strange behavior in Firefox, width() returns 0, for your and my plugin both. And on top of that it never factors in padding. jsfiddle.net/67cgB. I'm having the ...
Programmatically obtain the phone number of the Android phone
How can I programmatically get the phone number of the device that is running my android app?
17 Answers
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How to override the properties of a CSS class using another CSS class
...round: none; }
wins simply by order, i.e. by being after an otherwise equally “powerful” rule. But this imposes restrictions and requires you to be careful in any reorganization of style sheets.
These are all examples of the CSS Cascade, a crucial but widely misunderstood concept. It defines ...
Outline effect to text
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There is an experimental webkit property called text-stroke in CSS3, I've been trying to get this to work for some time but have been unsuccessful so far.
What I have done instead is used the already supported text-shadow property (supported in Chrome, Firefox, Op...