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Why is SELECT * considered harmful?
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There are really three major reasons:
Inefficiency in moving data to the consumer. When you SELECT *, you're often retrieving more columns from the database than your application really needs to function. This causes more data to mov...
Event on a disabled input
... However, Firefox doesn't exhibit this behaviour, it just does nothing at all when you click on a disabled element.
I can't think of a better solution but, for complete cross browser compatibility, you could place an element in front of the disabled input and catch the click on that element. Here...
Change name of iPhone app in Xcode 4
...was posted just after I switched to XCode 4, and I am so glad I did! It really rocks, blows away MS Visual Studio .NET 2008 (my day job).
– Jay Imerman
Aug 2 '11 at 3:45
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MIT vs GPL license [closed]
...n your entire project that is using the GPL code also becomes GPL automatically. Which means, it must be open-sourced, and the recipient gets all the same rights as you - meaning, they can turn around and distribute it, modify it, sell it, etc. And that would include your proprietary code which woul...
What is the difference between Modal and Push segue in Storyboards?
...visual indication:
A modal Segue is just one VC presenting another VC modally. The VCs don't have to be part of a navigation controller and the VC being presented modally is generally considered to be a "child" of the presenting (parent) VC. The modally presented VC is usually sans any navigatio...
How do you add an array to another array in Ruby and not end up with a multi-dimensional result?
...(a1.length, *a2)
or append and flatten:
(a1 << a2).flatten! # a call to #flatten instead would return a new array
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Differences between Oracle JDK and OpenJDK
...a commercial license. You should now pay attention to which JDK you're installing as Oracle JDK without subscription could stop working. source
Ref: List of Java virtual machines
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When should I use a composite index?
...olumn_A )
But it will not (at least not directly, maybe it can help partially if there are no better indices) help for queries that need
index( column_A, column_C )
Notice how column_B is missing.
In your original example, a composite index for two dimensions will mostly benefit queries that q...
How should I use git diff for long lines?
...nment variable. If you don't mind about paging (for example, your terminal allows you to scroll back) you might try explicitly setting GIT_PAGER to empty to stop it using a pager. Under Linux:
$ GIT_PAGER='' git diff
Without a pager, the lines will wrap.
If your terminal doesn't support coloured...
How do I tell if a regular file does not exist in Bash?
... The unary operator -z tests for a null string, while -n or no operator at all returns True if a string is not empty. ~ ibm.com/developerworks/library/l-bash-test/index.html
– BlueCacti
May 5 '14 at 11:06
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