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How can I add a column that doesn't allow nulls in a Postgresql database?
I'm adding a new, "NOT NULL" column to my Postgresql database using the following query (sanitized for the Internet):
8 Ans...
Reverting single file in SVN to a particular revision
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If you just want the old file in your working copy:
svn up -r 147 myfile.py
If you want to rollback, see this "How to return to an older version of our code in subversion?".
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impro...
How do I get the object if it exists, or None if it does not exist?
...ls.Manager, create a safe_get like the code above and use that manager for my models. That way you can write: SomeModel.objects.safe_get(foo='bar').
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Node.js: what is ENOSPC error and how to solve?
...ce: npm 1.1.21 cannot write, ENOSPC in npm's repo in github.
Note I solved my problem in the way that described in above source. However, see Murali Krishna's answer, which is more comprehensive.
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How to center canvas in html5
...or a solution for a while now, but haven't found anything. Maybe it's just my search terms.
Well, I'm trying to make the canvas center according to the size of the browser window. The canvas is 800x600.
And if the window gets below 800x600, it should resize as well(but that's not very important at t...
How to make gradient background in android
...eate a gradient, you create an xml file in res/drawable. I am calling mine my_gradient_drawable.xml:
<?xml version="1.0" encoding="utf-8"?>
<shape xmlns:android="http://schemas.android.com/apk/res/android">
<gradient
android:type="linear"
android:angle="0"
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Seeding the random number generator in Javascript
...om numbers like so:
rand();
rand();
Alternatively, simply choose some dummy data to pad the seed with, and advance the generator a few times (12-20 iterations) to mix the initial state thoroughly. This is often seen in reference implementations of PRNGs, but it does limit the number of initial sta...
HTML5: Slider with two inputs possible?
... I like ionRangeSlider a little better than the jQuery UI slider myself: ionden.com/a/plugins/ion.rangeSlider/en.html
– Charlotte
May 18 '16 at 14:45
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How does HashSet compare elements for equality?
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@Simon_Weaver it is. I do want to somehow avoid it in my hypothetical feature I was proposing.
– nawfal
Feb 1 '17 at 3:24
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How to create directory automatically on SD card
I'm trying to save my file to the following location
FileOutputStream fos = new FileOutputStream("/sdcard/Wallpaper/"+fileName);
but I'm getting the exception java.io.FileNotFoundException
However, when I put the path as "/sdcard/" it works.
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