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How to implement a many-to-many relationship in PostgreSQL?
... -- explicit pk
);
I made a few adjustments:
The n:m relationship is normally implemented by a separate table - bill_product in this case.
I added serial columns as surrogate primary keys. In Postgres 10 or later consider an IDENTITY column instead. See:
Safely rename tables using serial primary...
Sublime Text 2: How to delete blank/empty lines
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Small suggestion use ^(\r|\n\r?) to cover all possible line breaks.
– Haris Krajina
Nov 7 '12 at 9:22
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Could not load type from assembly error
...ght be overriding the assembly that you think is being loaded? This is usually the result of an incorrect assembly being loaded, for me it means I usually have something in the GAC overriding the version I have in bin/Debug.
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How to update a pull request from forked repo?
...to that forked repo. I then opened a pull request. The pull request listed all the changes I wanted.
5 Answers
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Can I set background image and opacity in the same property?
... Yeah, the big problem with a PNG is the size. It is likely going to be really large. Now that we can specify opacity: ... in all browsers, it way better!
– Alexis Wilke
Jul 1 '17 at 23:49
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What exactly is Python's file.flush() doing?
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There's typically two levels of buffering involved:
Internal buffers
Operating system buffers
The internal buffers are buffers created by the runtime/library/language that you're programming against and is meant to speed things up by ...
Difference between DateTime and Time in Ruby
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Newer versions of Ruby (2.0+) do not really have significant differences between the two classes. Some libraries will use one or the other for historical reasons, but new code does not necessarily need to be concerned. Picking one for consistency is probably best,...
Use Font Awesome Icon in Placeholder
...possible to use Font Awesome Icon in a Placeholder? I read that HTML isn't allowed in a placeholder. Is there a workaround?
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How do I add a library project to Android Studio?
... well-known Android library is available in a Maven repository and its installation takes only one line of code in the app/build.gradle file:
dependencies {
compile 'com.jakewharton:butterknife:6.0.0'
}
Adding the library
Here is the full process of adding external Android library to our pr...
When to use Cast() and Oftype() in Linq
...ly the elements that can safely be cast to type x.
Cast - will try to cast all the elements into type x. if some of them are not from this type you will get InvalidCastException
EDIT
for example:
object[] objs = new object[] { "12345", 12 };
objs.Cast<string>().ToArray(); //throws InvalidCas...