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Android: upgrading DB version and adding new table
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1. About onCreate() and onUpgrade()
onCreate(..) is called whenever the app is freshly installed. onUpgrade is called whenever the app is upgraded and launched and the database version is not the same.
2. Incrementing the db version
You need a constructor like:
MyOpenHelp...
Why do we need virtual functions in C++?
... a rat."
So far so good, right? Animals eat generic food, cats eat rats, all without virtual.
Let's change it a little now so that eat() is called via an intermediate function (a trivial function just for this example):
// This can go at the top of the main.cpp file
void func(Animal *xyz) { xyz-...
Swift Beta performance: sorting arrays
...t))
// [-1, 0, 2, 2, 5, 8, 1234]
// [-1, 0, 2, 2, 5, 8, 1234]
Both are called in the same program as written.
var x_swift = CInt[](count: n, repeatedValue: 0)
var x_c = CInt[](count: n, repeatedValue: 0)
for var i = 0; i < n; ++i {
x_swift[i] = CInt(random())
x_c[i] = CInt(random())
}...
Using variables inside a bash heredoc
... the
lines in the here-document are not expanded. If word is unquoted, all
lines of the here-document are subjected to parameter expansion, command substitution, and arithmetic expansion. [...]
If you change your first example to use <<EOF instead of << "EOF" you'll find that i...
Do I need to explicitly call the base virtual destructor?
...the destructor again as virtual on the inheriting class, but do I need to call the base destructor?
7 Answers
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What are “named tuples” in Python?
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Named tuples are basically easy-to-create, lightweight object types. Named tuple instances can be referenced using object-like variable dereferencing or the standard tuple syntax. They can be used similarly to struct or other common record types...
How does Facebook disable the browser's integrated Developer Tools?
... link; ours is a little more complicated for no good reason.
Chrome wraps all console code in
with ((console && console._commandLineAPI) || {}) {
<code goes here>
}
... so the site redefines console._commandLineAPI to throw:
Object.defineProperty(console, '_commandLineAPI',
{...
How to use underscore.js as a template engine?
...y know good tutorials about how to use underscore.js for templating, especially for biginners who have less experience with advanced javascript. Thanks
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Get model's fields in Django
Given a Django model, I'm trying to list all of its fields. I've seen some examples of doing this using the _meta model attribute, but doesn't the underscore in front of meta indicate that the _meta attribute is a private attribute and shouldn't be accessed directly? ... Because, for example, the ...
Mongoose populate after save
I cannot manually or automatically populate the creator field on a newly saved object ... the only way I can find is to re-query for the objects I already have which I would hate to do.
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