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Which data type for latitude and longitude?
I am newbie to PostgreSQL and PostGIS. I want to store latitude and longitude values in PostgreSQL 9.1.1 database table. I will calculate distance between two points, find nearer points by using this location values.
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Filtering for empty or NULL names in a queryset
...e.objects.exclude(alias__isnull=True)
If you need to exclude null values and empty strings, the preferred way to do so is to chain together the conditions like so:
Name.objects.exclude(alias__isnull=True).exclude(alias__exact='')
Chaining these methods together basically checks each condition i...
Maintain the aspect ratio of a div with CSS
...rce: w3.org, emphasis mine)
Padding-bottom values for other aspect ratios and 100% width :
aspect ratio | padding-bottom value
--------------|----------------------
16:9 | 56.25%
4:3 | 75%
3:2 | 66.66%
8:5 | 62.5%
Placing content in ...
How to rename files and folder in Amazon S3?
Is there any function to rename files and folders in Amazon S3? Any related suggestions are also welcome.
19 Answers
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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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Why doesn't the height of a container element increase if it contains floated elements?
I would like to ask how height and float work. I have an outer div and an inner div that has content in it. Its height may vary depending on the content of the inner div but it seems that my inner div will overflow its outside div. What would be the proper way to do it?
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Update built-in vim on Mac OS X
...his line to your .bashrc or .profile:
alias vim='/path/to/your/own/vim'
and/or change your $PATH so that it looks into its location before the default location.
The best thing to do, in my opinion, is to simply download the latest MacVim which comes with a very complete vim executable and use it...
When should I release objects in -(void)viewDidUnload rather than in -dealloc?
...ontroller means that even when its view is removed from the view hierarchy and released to save memory, through which the subviews are also released by the view, they will not actually be deallocated because the UIViewController itself still contains its own outstanding retaining references to those...
Does using “new” on a struct allocate it on the heap or stack?
...ut where value type variables are allocated. That's a different question - and one to which the answer isn't just "on the stack". It's more complicated than that (and made even more complicated by C# 2). I have an article on the topic and will expand on it if requested, but let's deal with just the ...
Chaining multiple MapReduce jobs in Hadoop
...be passed in as arguments to your jobs with appropriate code to parse them and set up the parameters for the job.
I think that the above method might however be the way the now older mapred API did it, but it should still work. There will be a similar method in the new mapreduce API but i'm not sure...