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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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How to run the sftp command with a password from Bash script?
...up. However, since I don't have control over other host, I cannot generate and share RSA keys with the other host.
9 Answe...
Find the last element of an array while using a foreach loop in PHP
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$numItems = count($arr) trick is not needed and reduces readability - in PHP there is no performance penalty for accessing count($arr) each time. The reason is that items count is internally saved as special field in the array header and is not calculated on-the-fly. T...
How can i tell if an object has a key value observer attached
if you tell an objective c object to removeObservers: for a key path and that key path has not been registered, it cracks the sads. like -
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Importing data from a JSON file into R
...fically, the file is an array of JSON objects with string fields, objects, and arrays. The RJSON Package isn't very clear on how to deal with this http://cran.r-project.org/web/packages/rjson/rjson.pdf .
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How do I extract a sub-hash from a hash?
...:d=>:D}
h1 = Hash[h1.to_a - h2.to_a] # => {:a=>:A, :c=>:C}
And if you want to patch that into the Hash class:
class Hash
def extract_subhash(*extract)
h2 = self.select{|key, value| extract.include?(key) }
self.delete_if {|key, value| extract.include?(key) }
h2
end
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Error handling in getJSON calls
How can you handle errors in a getJSON call? Im trying to reference a cross-domain script service using jsonp, how do you register an error method?
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Error type 3 Error: Activity class {} does not exist
I have an IntelliJ Android project, that I successfully imported to Android Studio 0.4.0. It works perfectly if I don't change anything in manifest. However, when I want to change the launcher activity and run, it fails with this error:
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How and why do I set up a C# build machine? [closed]
...ct. I've proposed setting up a build machine which will do nightly builds and tests of the project, because I understand that this is a Good Thing. Trouble is, we don't have a whole lot of budget here, so I have to justify the expense to the powers that be. So I want to know:
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Naming “class” and “id” HTML attributes - dashes vs. underlines [closed]
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Use Hyphens to ensure isolation between your HTML and JavaScript.
Why? see below.
Hyphens are valid to use in CSS and HTML but not for JavaScript Objects.
A lot of browsers register HTML Ids as global objects on the window/document object, in big projects, this can become...