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How do I (or can I) SELECT DISTINCT on multiple columns?
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edited Sep 10 '08 at 15:55
answered Sep 10 '08 at 15:36
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What's an object file in C?
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An object file is the real output from the compilation phase. It's mostly machine code, but has...
Conditionally ignoring tests in JUnit 4
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edited Dec 7 '17 at 2:01
tkruse
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answered Nov...
What kind of virtual machine is BEAM (the Erlang VM)?
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edited Jul 20 '16 at 1:29
Ilya Vassilevsky
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How to get number of rows using SqlDataReader in C#
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answered Sep 5 '09 at 13:25
Henk HoltermanHenk Holterman
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What are detached, persistent and transient objects in hibernate?
...ession later though).
All this is clearly explained in the whole Chapter 10. Working with objects of the Hibernate documentation that I'm only paraphrasing above. Definitely, a must-read.
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Get JavaScript object from array of objects by value of property [duplicate]
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answered Dec 20 '12 at 2:01
elclanrselclanrs
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How does MongoDB sort records when no sort order is specified?
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What is the default sort order when none is specified?
The default internal sort order (or natu...
Does setting Java objects to null do anything anymore?
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answered May 12 '09 at 3:11
Neil CoffeyNeil Coffey
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Create an empty data.frame
... stringsAsFactors=FALSE)
str(df)
> str(df)
'data.frame': 0 obs. of 5 variables:
$ Doubles : num
$ Ints : int
$ Factors : Factor w/ 0 levels:
$ Logicals : logi
$ Characters: chr
N.B. :
Initializing a data.frame with an empty column of the wrong type does not ...