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Is an index needed for a primary key in SQLite?
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It does it for you.
INTEGER PRIMARY KEY columns aside, both UNIQUE and PRIMARY KEY
constraints are implemented by creating an index in the database (in
the same way as a "CREATE UNIQUE INDEX" statement would). Such an
index is used like any other index in the database to optimize
que...
How to programmatically send SMS on the iPhone?
Does anybody know if it's possible, and how, to programmatically send a SMS from the iPhone , with the official SDK / Cocoa Touch?
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How to encode the filename parameter of Content-Disposition header in HTTP?
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There is discussion of this, including links to browser testing and backwards compatibility, in the proposed RFC 5987, "Character Set and Language Encoding for Hypertext Transfer Protocol (HTTP) Header Field Parameters."
RFC 2183 indicates that such headers should be encoded according to...
Is there a Java reflection utility to do a deep comparison of two objects?
...te unit tests for a variety of clone() operations inside a large project and I'm wondering if there is an existing class somewhere that is capable of taking two objects of the same type, doing a deep comparison, and saying if they're identical or not?
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What is the easiest way to remove the first character from a string?
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p asdf
# >> "12,23,987,43"
I'm always looking for the fastest and most readable way of doing things:
require 'benchmark'
N = 1_000_000
puts RUBY_VERSION
STR = "[12,23,987,43"
Benchmark.bm(7) do |b|
b.report('[0]') { N.times { "[12,23,987,43"[0] = '' } }
b.report('sub') { N.time...
How do you remove a Cookie in a Java Servlet
...ation:
A negative value means that the cookie is not stored persistently and will be deleted when the Web browser exits. A zero value causes the cookie to be deleted.
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Is there any use for unique_ptr with array?
...ocators. Some people need a dynamically sized array, so std::array is out. And some people get their arrays from other code that is known to return an array; and that code isn't going to be rewritten to return a vector or something.
By allowing unique_ptr<T[]>, you service those needs.
In sh...
How to delete a word and go into insert mode in Vim?
...mal mode I can hit Ctrl + E which deletes the rest of the current word and goes to insert mode.
5 Answers
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Why does += behave unexpectedly on lists?
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The general answer is that += tries to call the __iadd__ special method, and if that isn't available it tries to use __add__ instead. So the issue is with the difference between these special methods.
The __iadd__ special method is for an in-place addition, that is it mutates the object that it a...
When is it right for a constructor to throw an exception?
...hat supports one-stage construction, where the object is fully initialized and usable after construction.
One-stage constructors should throw if they fail to fully initialize the object. If the object cannot be initialized, it must not be allowed to exist, so the constructor must throw.
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