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How to set auto increment primary key in PostgreSQL?
I have a table in PostgreSQL with 22 columns, and I want to add an auto increment primary key.
7 Answers
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Unresolved Import Issues with PyDev and Eclipse
I am very new to PyDev and Python, though I have used Eclipse for Java plenty. I am trying to work through some of the Dive Into Python examples and this feels like an extremely trivial problem that's just becoming exceedingly annoying. I am using Ubuntu Linux 10.04.
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How do I compute derivative using Numpy?
...es
Automatic Derivatives
Symbolic Differentiation
Compute derivatives by hand.
Finite differences require no external tools but are prone to numerical error and, if you're in a multivariate situation, can take a while.
Symbolic differentiation is ideal if your problem is simple enough. Symbolic...
Encode URL in JavaScript?
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Check out the built-in function encodeURIComponent(str) and encodeURI(str).
In your case, this should work:
var myOtherUrl =
"http://example.com/index.html?url=" + encodeURIComponent(myUrl);
shar...
What are enums and why are they useful?
Today I was browsing through some questions on this site and I found a mention of an enum being used in singleton pattern about purported thread safety benefits to such solution.
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jQueryUI Tooltips are competing with Twitter Bootstrap
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Both jQuery UI and Bootstrap use tooltip for the name of the plugin. Use $.widget.bridge to create a different name for the jQuery UI version and allow the Bootstrap plugin to stay named tooltip (trying to use the noConflict option on the B...
In Django - Model Inheritance - Does it allow you to override a parent model's attribute?
... is to create an abstract model representing a "Place", eg. AbstractPlace, and inherit from it:
class AbstractPlace(models.Model):
name = models.CharField(max_length=20)
rating = models.DecimalField()
class Meta:
abstract = True
class Place(AbstractPlace):
pass
class Long...
Do you need to dispose of objects and set them to null?
Do you need to dispose of objects and set them to null, or will the garbage collector clean them up when they go out of scope?
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Position of least significant bit that is set
...hed. My favourite solution for your problem (from that site) is «multiply and lookup»:
unsigned int v; // find the number of trailing zeros in 32-bit v
int r; // result goes here
static const int MultiplyDeBruijnBitPosition[32] =
{
0, 1, 28, 2, 29, 14, 24, 3, 30, 22, 20, 15, 25, 17...
What is the default location for MSBuild logs?
... location of the log file? I have searched in the folder where my solution and projects are stored, but cannot find any .log file.
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