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SQL, Postgres OIDs, What are they and why are they useful?
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OIDs basically give you a built-in id for every row, contained in a system column (as opposed to a user-space column). That's handy for tables where you don't have a primary key, have duplicate rows, etc. For example, if you...
what is faster: in_array or isset? [closed]
...y value until it finds a match.
Being an opcode, it has less overhead than calling the in_array built-in function.
These can be demonstrated by using an array with values (10,000 in the test below), forcing in_array to do more searching.
isset: 0.009623
in_array: 1.738441
This builds on Jaso...
What is the difference between a process and a thread?
...erating environment feature, rather than a CPU feature (though the CPU typically has operations that make threads efficient).
Erlang uses the term "process" because it does not expose a shared-memory multiprogramming model. Calling them "threads" would imply that they have shared memory.
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How to serve static files in Flask
...xample below, I have moved my templates and static files into a sub-folder called web.
app = Flask(__name__,
static_url_path='',
static_folder='web/static',
template_folder='web/templates')
static_url_path='' removes any preceding path from the URL (i.e.
the ...
TypeScript with KnockoutJS
...is why we use definition files for code written in JavaScript so as to provide typescript type checking. Of course you could declare libs as "any", but this is not good.hope I helped!
– George Mavritsakis
Dec 1 '12 at 16:03
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How to output something in PowerShell
...e aforementioned value, and being the last item on the command pipeline it calls the .toString() method and outputs the result to STDOUT (by default). A thing of beauty.
The other Write-* commands are specific to outputting the text to their associated streams, and have their place as such.
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How do you pass custom environment variable on Amazon Elastic Beanstalk (AWS EBS)?
...ng the configuration files. Create a directory at the root of your project called
.ebextensions/
Then create a file called environment.config (this file can be called anything but it must have the .config extension) and add the following values
option_settings:
- option_name: CUSTOM_ENV
va...
Argument list too long error for rm, cp, mv commands
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No, xargs specifically splits up the list and issues several commands if necessary.
– tripleee
Jul 2 '12 at 7:50
7
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Does Java have a HashMap with reverse lookup?
... to be one of the implementations of BidiMap.
As a mathematician, I would call this kind of structure a bijection.
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Should an Enum start with a 0 or a 1?
...ines:
✔️ DO provide a value of zero on simple enums.
Consider calling the value something like "None." If such a value is not appropriate for this particular enum, the most common default value for the enum should be assigned the underlying value of zero.
Framework Design Guidelines /...