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SQL JOIN - WHERE clause vs. ON clause
... JOIN OrderLines ON OrderLines.OrderID=Orders.ID
WHERE Orders.ID = 12345
and
SELECT *
FROM Orders
LEFT JOIN OrderLines ON OrderLines.OrderID=Orders.ID
AND Orders.ID = 12345
The first will return an order and its lines, if any, for order number 12345. The second will return all orders, but...
adb not finding my device / phone (MacOS X)
Doing Android development on a Mac and this very new phone I have doesn't show up in the devices list in adb . Lots of other phones and devices work fine for me so I know my setup is good.
...
List of standard lengths for database fields
I'm designing a database table and once again asking myself the same stupid question: How long should the firstname field be?
...
How can I add new keys to a dictionary?
...y by assigning a value
to that key. If the key doesn't exist, it's added and points to that
value. If it exists, the current value it points to is overwritten.
—R. Navega
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Assign an initial value to radio button as checked
...
@matthewh - nah, you can use just "checked" on it's own and it is valid HTML (although not valid XHTML). Personally I prefer 'checked="checked"', but you don't have to use it ... indeed, there's quite a strong case against using it.
– Algy Taylor
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How do I use Ruby for shell scripting?
...
By default, you already have access to Dir and File, which are pretty useful by themselves.
Dir['*.rb'] #basic globs
Dir['**/*.rb'] #** == any depth of directory, including current dir.
#=> array of relative names
File.expand_path('~/file.txt') #=> "/User/mat/...
Pimpl idiom vs Pure virtual class interface
...would make a programmer to choose either Pimpl idiom or pure virtual class and inheritance.
10 Answers
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What's the best way of implementing a thread-safe Dictionary?
...e to implement a thread-safe Dictionary in C# by deriving from IDictionary and defining a private SyncRoot object:
8 Answer...
Xcode - How to fix 'NSUnknownKeyException', reason: … this class is not key value coding-compliant f
...n once off practice apps. Naming collisions can be very hard to track down and you don't want to waste the time.
Another possible reason for this error: when copying & pasting elements from one controller into another, Xcode somehow keeps that link to the original controller, even after editin...
Execution time of C program
...Windows machines (from the Win98 era) it was closer to 60ms.
clock() is standard C; it works "everywhere". There are system-specific functions, such as getrusage() on Unix-like systems.
Java's System.currentTimeMillis() does not measure the same thing. It is a "wall clock": it can help you measure...