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ActiveRecord: size vs count
In Rails, you can find the number of records using both Model.size and Model.count . If you're dealing with more complex queries is there any advantage to using one method over the other? How are they different?
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Pointers, smart pointers or shared pointers? [duplicate]
...ting/copying/destructing a shared pointer needs to be an atomic operation, and this can hinder performance if you have many threads running. However, it won't always be the case - only testing will tell you for sure.
There is an argument (that I like) against shared pointers - by using them, you ar...
How to install plugins to Sublime Text 2 editor?
...ublime Text 2 install directory.
All you need to do is download the plugin and put the plugin folder in the Packages folder.
Or, an easier way would be to install the Package Control Plugin by wbond.
Just go here: https://sublime.wbond.net/installation
and follow the install instructions.
Once y...
What is the difference between a static and a non-static initialization code block
...static from the initializer block, it then becomes an instance initializer and so int a is initialized at construction.
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Converting from a string to boolean in Python?
...ref.html#distutils.util.strtobool
True values are y, yes, t, true, on and 1; false values are n, no, f, false, off and 0. Raises ValueError if val is anything else.
Be aware that distutils.util.strtobool() returns integer representations and thus it needs to be wrapped with bool() to get Bool...
How to check if object has any properties in JavaScript?
...ws:
for(var prop in ad) {
if (ad.hasOwnProperty(prop)) {
// handle prop as required
}
}
It is important to use the hasOwnProperty() method, to determine whether the object has the specified property as a direct property, and not inherited from the object's prototype chain.
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How do I list the functions defined in my shell?
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declare -F
Function names and definitions may be listed with the -f option to the
declare builtin command (see Bash Builtins). The -F option to declare
will list the function names only
(and optionally the source file and line number).
Bash Re...
PDO mysql: How to know if insert was successful
I'm using PDO to insert a record (mysql and php)
7 Answers
7
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What is /dev/null 2>&1?
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>> /dev/null redirects standard output (stdout) to /dev/null, which discards it.
(The >> seems sort of superfluous, since >> means append while > means truncate and write, and either appending to or writing to /dev/null has the same n...
What, exactly, is needed for “margin: 0 auto;” to work?
...lement is used to centre it (left-right). However, I know that the element and its parent must meet certain criteria for the auto margin to work, and I can never seem to get the magic right.
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