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what is the difference between GROUP BY and ORDER BY in sql
... returned.
GROUP BY will aggregate records by the specified columns which allows you to perform aggregation functions on non-grouped columns (such as SUM, COUNT, AVG, etc).
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How to select where ID in Array Rails ActiveRecord without exception
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If it is just avoiding the exception you are worried about, the "find_all_by.." family of functions works without throwing exceptions.
Comment.find_all_by_id([2, 3, 5])
will work even if some of the ids don't exist. This works in the
user.comments.find_all_by_id(potentially_nonexistent_id...
A more pretty/informative Var_dump alternative in PHP? [closed]
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A full year of time and labor after asking this, I've finally open sourced my version of var_dump, Kint. Read about it in the project page, or directly in github.
Here's a screenshot:
Sorry for the plug :)
EDIT: I'd just like to remind the commenters, that this is not a supp...
How do you load custom UITableViewCells from Xib files?
... simple: How do you load custom UITableViewCell from Xib files? Doing so allows you to use Interface Builder to design your cells. The answer apparently is not simple due to memory managment issues. This thread mentions the issue and suggests a solution, but is pre NDA-release and lacks code. He...
Asynchronous vs synchronous execution, what does it really mean? [closed]
...pt of doing two things at one time. The operating system simulates this by allocating slices of time to different threads.
Now, if you introduce multiple cores/processors into the mix, then things CAN actually happen at the same time. The operating system can allocate time to one thread on the firs...
How to do SELECT COUNT(*) GROUP BY and ORDER BY in Django?
I'm using a transaction model to keep track all the events going through the system
2 Answers
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Custom fonts in iOS 7
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First of all I'm assuming that SpriteKit doesn't make any difference.
You need your font in .otf or .ttf copied to your project. For example in Supporting Files.
You need to edit .plist file. Add "Fonts provided by application" key ...
How can I disable a button in a jQuery dialog from a function?
...tinue" button. I would like this "continue" button to only be enabled once all the fields have content in them, else it will remain disabled.
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Reintegrate can only be used if revisions X through Y were previously merged from to reintegra
Been using SVN branches with Tortoise 1.6. I've been periodically merging the trunk into the branch to keep it up to date.
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How do you clone an Array of Objects in Javascript?
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The issue with your shallow copy is that all the objects aren't cloned. While the references to each object are unique in each array, once you ultimately grab onto it you're dealing with the same object as before. There is nothing wrong with the...