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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...
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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Why is SCTP not much used/known
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Indeed, SCTP is used mostly in the telecom area. Traditionally, telecom switches use SS7 (Signaling System No. 7) to interconnect different entities in the telecom network. For example - the telecom provider's subscriber data base(HLR), with a switch (MSC), the subscriber is connect...
jQuery - checkbox enable/disable
...ve a bunch of checkboxes like this. If the "Check Me" checkbox is checked, all the other 3 checkboxes should be enabled, else they should be disabled. How can I do this using jQuery?
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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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Can I add jars to maven 2 build classpath without installing them?
...the answers you'll find around the internet will suggest you to either install the dependency to your local repository or specify a "system" scope in the pom and distribute the dependency with the source of your project. But both of these solutions are actually flawed.
Why you shouldn't apply the "I...
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...