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Many-to-many relationship with the same model in rails?
...l associations eg: postA.update_attributes({:post_b_ids =>[2,3,4]}) any idea or workarounds ?
– Lohith MV
Mar 27 '12 at 14:21
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Principles for Modeling CouchDB Documents
...
Thanks for getting into it with me a bit. I get the idea of "include all data that is needed to display a page regarding the item in question", but that is still very difficult to implement. A "page" could be a page of Comments, a page of Users, a page of Posts, or a page of ...
What are bitwise shift (bit-shift) operators and how do they work?
...overflow). So unless you need arithmetic right shift, it's usually a good idea to do your bit-shifting with unsigned types.)
Left shift (<<)
Integers are stored, in memory, as a series of bits. For example, the number 6 stored as a 32-bit int would be:
00000000 00000000 00000000 00000110
S...
java.sql.SQLException: - ORA-01000: maximum open cursors exceeded
...to be hard to call the close() method on it.
However, it is rarely a good idea to attempt to control when the GC is run (Weak, Soft and PhantomReferences let you know after the fact that the object is enqueued for GC). In fact, if the amount of memory in the JVM is large (eg -Xmx2000m) you might ne...
What is the explanation for these bizarre JavaScript behaviours mentioned in the 'Wat' talk for Code
... {} + []. This is part of the overall 'wat'-ness of Javascript.
The basic idea was simple JavaScript wanted to allow both of these forms:
if (u)
v;
if (x) {
y;
z;
}
To do so, two interpretations were made of the opening brace: 1. it is not required and 2. it can appear anywhere.
Th...
How to import multiple .csv files at once?
...would include a benchmark if you are going to say something is faster. One idea is creating 30 1GB files and reading them, that would be a case where performance matters.
– marbel
Mar 16 '18 at 3:26
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Why is the gets function so dangerous that it should not be used?
... variables if the buffer is statically allocated. None of these is a good idea — they epitomize the phrase 'undefined behaviour`.
There is also the TR 24731-1 (Technical Report from the C Standard Committee) which provides safer alternatives to a variety of functions, including gets():
§6...
A gentle tutorial to Emacs/Swank/Paredit for Clojure
...t found out that the best option is Emacs even if I don't really liked it. IDEA, Eclipse and netbeans simply doesn't fit in the picture.
– Adam Arold
Dec 13 '11 at 22:26
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Java's Virtual Machine and CLR
...the runtime performance of a computer program. JIT builds upon two earlier ideas in run-time environments: bytecode compilation and dynamic compilation. It converts code at runtime prior to executing it natively, for example bytecode into native machine code. The performance improvement over interpr...
Hibernate vs JPA vs JDO - pros and cons of each? [closed]
...ome notes:
JDO and JPA are both specifications, not implementations.
The idea is you can swap JPA implementations, if you restrict your code to use standard JPA only. (Ditto for JDO.)
Hibernate can be used as one such implementation of JPA.
However, Hibernate provides a native API, with features ...