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Select first row in each GROUP BY group?
... BY p.customer) y ON y.customer = x.customer
AND y.max_total = x.total
GROUP BY x.customer, x.total
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What is the $? (dollar question mark) variable in shell scripting? [duplicate]
I'm trying to learn shell scripting, and I need to understand someone else's code. What is the $? variable hold? I can't Google search the answer because they block punctuation characters.
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Admob Error in Eclipse for android:configChanges
Eclipse is giving me an error on the android:configChanges line in my AndroidManifest.xml:
7 Answers
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How to do an update + join in PostgreSQL?
... -- joined table
WHERE
a.abiturient_id = b.id AND -- JOIN ON clause
a.documents_taken_at::date < b.certificate_issued_at -- Subquery WHERE
As you can see, original subquery JOIN's ON clause have become one of WHERE conditions, which is ...
Why does calling a method in my derived class call the base class method?
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There's a difference between new and virtual/override.
You can imagine, that a class, when instantiated, is nothing more than a table of pointers, pointing to the actual implementation of its methods. The following image should visualize this pretty well:
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Determine if a function exists in bash
...t tests which are executed from bash. Unit tests are initialized, executed and cleaned up in a bash script. This script usualy contains an init(), execute() and cleanup() functions. But they are not mandatory. I'd like to test if they are or are not defined.
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Is it good practice to use java.lang.String.intern()?
... that you're going to compare. It's easy to forget to intern() all strings and then you can get confusingly incorrect results. Also, for everyone's sake, please be sure to very clearly document that you're relying on the strings being internalized.
The second disadvantage if you decide to internali...
'transform3d' not working with position: fixed children
... none for the transform results in the creation of both a stacking context and a containing block. The object acts as a containing block for fixed positioned descendants.
This means that fixed positioning becomes fixed to the transformed element, rather than the viewport.
There's not currently ...
Any open source alternatives to balsamiq mockup [closed]
...ource mock up tool is Pencil. Its available as firefox plugin as well as stand alone.
Another solution, which I personally use is Inkscape, an open source SVG Editor. It is NOT a mock up designer, but we can use it for designing mock ups, using freely available stencil kit, like Yahoo Stencil Kit....
Display HTML snippets in HTML
...ippets on a webpage without needing to replace each < with &lt; and > with &gt; ?
25 Answers
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