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What's the fastest way to do a bulk insert into Postgres?
I need to programmatically insert 10's of millions of records into a postgres database. Presently I am executing 1000's of insert statements in a single "query".
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Multiline Comment Workarounds?
...ly, see for example this recent thread on r-help. The consensus answer usually is the one shown above: that given that the language has no direct support, you have to either
work with an editor that has region-to-comment commands, and most advanced R editors do
use the if (FALSE) constructs sugg...
How to import a class from default package
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Wow I really don't know java at all. That was a great help. Guess I'll have to move my class into a package...
– anhoppe
Jan 20 '16 at 20:14
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Convert System.Drawing.Color to RGB and Hex Value
...t be null and c.R.ToString(), c.G.ToString(), and c.B.ToString() can't actually fail (the only way I can see them failing is with a NullReferenceException, and none of them can actually be null).
You could clean the whole thing up using the following:
private static String HexConverter(System.Draw...
Creating temporary files in Android
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This is what I typically do:
File outputDir = context.getCacheDir(); // context being the Activity pointer
File outputFile = File.createTempFile("prefix", "extension", outputDir);
As for their deletion, I am not complete sure either. Since I ...
Is there a way to add/remove several classes in one single instruction with classList?
... And if you want to apply an Array of several class-names, you have to call: DOMTokenList.prototype.add.apply(elem.classList, ['first', 'second', 'third']);
– Emanuel Kluge
Feb 15 '13 at 16:36
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Convert hex to binary
...gits and leading zeroes).
Short answer:
The new f-strings in Python 3.6 allow you to do this using very terse syntax:
>>> f'{0xABC123EFFF:0>42b}'
'001010101111000001001000111110111111111111'
or to break that up with the semantics:
>>> number, pad, rjust, size, kind = 0xAB...
How to suppress GCC warnings from library headers?
...ncludes (i.e. #include ) or includes from certain paths? I'd like to use -Wall and/or -Wextra as usual on project code without relevant info being obscured. I currently use grep on make output but I'd like something better.
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How to define a List bean in Spring?
... stages in my application. It's configured that the necessary class (here called Configurator ) is injected with the stages.
Now I need the List of Stages in another class, named LoginBean . The Configurator doesn't offer access to his List of Stages.
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How can I create an Asynchronous function in Javascript?
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You cannot make a truly custom asynchronous function. You'll eventually have to leverage on a technology provided natively, such as:
setInterval
setTimeout
requestAnimationFrame
XMLHttpRequest
WebSocket
Worker
Some HTML5 APIs such as the File API, Web Database API
Technologies that support...