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What is the PostgreSQL equivalent for ISNULL()
...ited Jan 14 '12 at 2:28
Erwin Brandstetter
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answered Feb 6 '10 at 20:02
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Difference between validate(), revalidate() and invalidate() in Swing GUI
...idate() marks the container as invalid. Means the content is somehow wrong and must be re-laid out. But it's just a kind of mark/flag. It's possible that multiple invalid containers must be refreshed later.
validate() performs relayout. It means invalid content is asked for all the sizes and all th...
Entity Framework 4 - AddObject vs Attach
I have been working with Entity Framework 4 recently, and am slightly confused as to when to use ObjectSet.Attach , and ObjectSet.AddObject .
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Ruby's ||= (or equals) in JavaScript?
...s ||= mechanism. If a variable doesn't exist or is nil , then create it and set it equal to something:
6 Answers
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Convert a timedelta to days, hours and minutes
I've got a timedelta. I want the days, hours and minutes from that - either as a tuple or a dictionary... I'm not fussed.
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Extracting bits with a single multiplication
I saw an interesting technique used in an answer to another question , and would like to understand it a little better.
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How can I combine hashes in Perl?
...he best way to combine both hashes into %hash1? I always know that %hash2 and %hash1 always have unique keys. I would also prefer a single line of code if possible.
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Gcc error: gcc: error trying to exec 'cc1': execvp: No such file or directory
... 12. Now I am getting an error. I have recently been doing some .so builds and installed Clang not to long ago, but have successfully compiled since both of those events, so not sure what has changed. I used the GUI Software Manager to remove and then install gcc again, but the results are the same:...
What is difference between width, innerWidth and outerWidth, height, innerHeight and outerHeight in
... to see what is the difference, but they display me same results for width and height.
6 Answers
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R object identification
... often ending up with a function producing output for which I don't understand the output data type. I'm expecting a list and it ends up being a list of lists or a data frame or something else. What's a good method or workflow for figuring out the output data type when first using a function?
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