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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...
Is inline assembly language slower than native C++ code?
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Yes, most times.
First of all you start from wrong assumption that a low-level language (assembly in this case) will always produce faster code than high-level language (C++ and C in this case). It's not true. Is C code always faster than Java code? N...
What is the “__v” field in Mongoose
... now, but I wanted something that I could put in the Schema directly so in all queries.
– diosney
Mar 24 '14 at 11:52
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What is a regular expression which will match a valid domain name without a subdomain?
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This should match all cases I think: ^([a-z0-9])(([a-z0-9-]{1,61})?[a-z0-9]{1})?(\.[a-z0-9](([a-z0-9-]{1,61})?[a-z0-9]{1})?)?(\.[a-zA-Z]{2,4})+$
– transilvlad
May 16 '13 at 16:38
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How to parse/read a YAML file into a Python object? [duplicate]
...ame: Node 2
branch2-1:
name: Node 2-1
And you've installed PyYAML like this:
pip install PyYAML
And the Python code looks like this:
import yaml
with open('tree.yaml') as f:
# use safe_load instead load
dataMap = yaml.safe_load(f)
The variable dataMap now contains...
Why is there no xrange function in Python3?
...Some performance measurements, using timeit instead of trying to do it manually with time.
First, Apple 2.7.2 64-bit:
In [37]: %timeit collections.deque((x for x in xrange(10000000) if x%4 == 0), maxlen=0)
1 loops, best of 3: 1.05 s per loop
Now, python.org 3.3.0 64-bit:
In [83]: %timeit collec...
Syntax Error: Not a Chance
...ng blocks by braces instead of indentation will never be implemented.
Normally, imports from the special __future__ module enable features that are backwards-incompatible, such as the print() function, or true division.
So the line from __future__ import braces is taken to mean you want to enable ...
Detecting Unsaved Changes
...reunload methods as required.
From the comments, the following references all input fields, without duplicating code:
$(':input').change(function () {
Using $(":input") refers to all input, textarea, select, and button elements.
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How to remove an item from an array in AngularJS scope?
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Your issue is not really with Angular, but with Array methods. The proper way to remove a particularly item from an array is with Array.splice. Also, when using ng-repeat, you have access to the special $index property, which is the current inde...
How can I implement a tree in Python?
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I came across this answer via Google. This library is really nice. I especially love the ability to use the mixin class to make an tree of any object!
– Rÿck Nöthing
Mar 8 '19 at 1:21
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