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Adding a new value to an existing ENUM Type
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It's worth mentioning that this can all be done in a single transaction, so it's mostly safe to do it in a production database.
– David Leppik
Jul 8 '11 at 20:41
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Difference between Node object and Element object?
I am totally confused between Node object and Element object.
document.getElementById() returns Element object while document.getElementsByClassName()
returns NodeList object(Collection of Elements or Nodes?)
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How to make a variadic macro (variable number of arguments)
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The reason for ## before VA_ARGS is that it swallows the preceding comma in case the variable-argument list is empty, eg. FOO("a") expands to printf("a"). This is an extension of gcc (and vc++, maybe), C99 requires at least one argument to be present in place of the elli...
Convert a row of a data frame to vector
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Might have been changed in the meantime, but today unlist allows dropping names: identical(unlist(df[1,], use.names = FALSE), as.numeric(df[1,])) (and btw df still is not a sensible name for a data.frame... ;-))
– Andri Signorell
Sep 25 '1...
Get model's fields in Django
Given a Django model, I'm trying to list all of its fields. I've seen some examples of doing this using the _meta model attribute, but doesn't the underscore in front of meta indicate that the _meta attribute is a private attribute and shouldn't be accessed directly? ... Because, for example, the ...
Rails raw SQL example
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and then you'd need to call values on this PG::Result object to get the results array
– jobwat
Mar 26 '14 at 1:00
3
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ARC and bridged cast
...__bridge_transfer? Otherwise it would seem that the moment CFRelease() is called the object is gone and points to nothing. Similarly, when you use __bridge_retain, does ARC reduce the op's retain count by 1? Else it seems that the object would never be properly released.
– Tony...
window.close and self.close do not close the window in Chrome
...ec for window.close():
The close() method on Window objects should, if all the following conditions are met, close the browsing context A:
The corresponding browsing context A is script-closable.
The browsing context of the incumbent script is familiar with the browsing context A.
Th...
Web API Put Request generates an Http 405 Method Not Allowed error
Here's the call to the PUT method on my Web API - the third line in the method (I am calling the Web API from an ASP.NET MVC front end):
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Getter and Setter declaration in .NET [duplicate]
... a plain field:
public string MyField
But this field can be accessed by all outside users of your class. People can insert illegal values or change the value in ways you didn't expect.
By using a property, you can encapsulate the way your data is accessed. C# has a nice syntax for turning a fiel...