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Can a foreign key be NULL and/or duplicate?
...at field must exist first in a different table (the parent table). That is all an FK is by definition. Null by definition is not a value. Null means that we do not yet know what the value is.
Let me give you a real life example. Suppose you have a database that stores sales proposals. Suppose furth...
How to change the font size on a matplotlib plot
How does one change the font size for all elements (ticks, labels, title) on a matplotlib plot?
12 Answers
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Moq: Invalid setup on a non-overridable member: x => x.GetByTitle(“asdf”)
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because the call to GetArticleDAO from the factory returns ArticleDAO not IArticleDAO, b/c articleDAO also binds to an abstract class that has nhibernate stuff in it.
– mrblah
Dec 25 '09 at 21:57
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How to check if object has any properties in JavaScript?
...d Apr 20 '10 at 6:49
Daniel VassalloDaniel Vassallo
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SVN (Subversion) Problem “File is scheduled for addition, but is missing” - Using Versions
...p into the cold water and fire up your hidden Mac command shell :-) (it's called "Terminal" in the german OSX, no idea how to bring it up in the english version...)
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Difference between Property and Field in C# 3.0+
...ld into a property and add an private backing field? How does this affect calling code?
– Serge Wautier
Mar 17 '09 at 9:45
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How are multi-dimensional arrays formatted in memory?
In C, I know I can dynamically allocate a two-dimensional array on the heap using the following code:
6 Answers
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RESTful call in Java
I am going to make a RESTful call in Java. However, I don't know how to make the call. Do I need to use the URLConnection or others? Can anyone help me. thank you.
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indexOf method in an object array?
... think to see the performance of this method vs. a simple for loop. Especially when you're running on a mobile platform with limited resources.
– Doug
Aug 17 '15 at 5:51
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How to copy from CSV file to PostgreSQL table with headers in CSV file?
... @Daniel I understood the user's table already existed and had all the columns they needed and that they wanted to simply ADD data.
– G. Cito
Jul 28 '14 at 16:16
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