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What is the difference between HAVING and WHERE in SQL?
...nt(1)
From Address
Where State = 'MA'
Group By City
Gives you a table of all cities in MA and the number of addresses in each city.
This code:
select City, CNT=Count(1)
From Address
Where State = 'MA'
Group By City
Having Count(1)>5
Gives you a table of cities in MA with more than 5 address...
Sending a message to nil in Objective-C
...I wonder what " sending a message to nil " means - let alone how it is actually useful. Taking an excerpt from the documentation:
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Prevent the keyboard from displaying on activity start
...g both in code, and in xml! Indeed, this is the most correct answer! Especially since it was probably that 3 minutes you spent writing both methods that made you not first ;-)
– eric
Apr 21 '17 at 1:13
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Automatically update version number
...ce the revision and build numbers with a coded date/timestamp, which is usually also a good way.
For more info, see the Assembly Linker Documentation in the /v tag.
As for automatically incrementing numbers, use the AssemblyInfo Task:
AssemblyInfo Task
This can be configured to automatically in...
Overriding a JavaScript function while referencing the original
...tioned in the comments, be sure to include the () at the end. You want to call the outer function and store the result (one of the two inner functions) in a, not store the outer function itself in a.
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Save An Image To Application Documents Folder From UIView On IOS
I have a UIImageView that allows a user to place and hold an image until it can be saved. The problem is, I can't figure out how to actually save and retrieve the image I've placed in the view.
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Intent - if activity is running, bring it to front, else start a new one (from notification)
...recent task and click it, it will onResume(); Cant I onResume() programatically.
– user9599745
Jan 29 at 20:58
@Javene...
How can I count occurrences with groupBy?
...answered Jun 5 '17 at 21:37
user_3380739user_3380739
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Execute bash script from URL
...the advantage of using that initial redirection? I ask because for RVM installation, they use the command: bash < <(curl -s https://rvm.beginrescueend.com/install/rvm) Why not just: bash <(curl -s https://rvm.beginrescueend.com/install/rvm)
– Tristan
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How can I check if a URL exists via PHP?
...side.
Waiting for a response might take time and block code execution.
Not all headers returned by get_headers() are well formed.
Use curl (if you can).
Prevent fetching the entire body/content, but only request the headers.
Consider redirecting urls:
Do you want the first code returned?
Or follow a...