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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...
What does Java option -Xmx stand for? [duplicate]
...B. The upper limit for this value will be approximately 4000m on Solaris 7 and Solaris 8 SPARC platforms and 2000m on Solaris 2.6 and x86 platforms, minus overhead amounts. Examples:
-Xmx83886080
-Xmx81920k
-Xmx80m
So, in simple words, you are setting Java heap m...
for each loop in Objective-C for accessing NSMutable dictionary
I am finding some difficulty in accessing mutable dictionary keys and values in Objective-C.
7 Answers
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Serializing object that contains cyclic object value
...beware of using, very potential crashes your app. needs correct semicolons and is not useable on event objects!
– Ol Sen
Apr 22 '13 at 16:07
3
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MySQL, better to insert NULL or empty string?
...a lot of different fields. Some of the fields are optional while some are mandatory. In my DB I have a table which holds all these values, is it better practice to insert a NULL value or an empty string into the DB columns where the user didn't put any data?
...
Why is the minimalist, example Haskell quicksort not a “true” quicksort?
...
The true quicksort has two beautiful aspects:
Divide and conquer: break the problem into two smaller problems.
Partition the elements in-place.
The short Haskell example demonstrates (1), but not (2). How (2) is done may not be obvious if you don't already know the technique!...
“int main (vooid)”? How does that work?
I recently had to type in a small C test program and, in the process, I made a spelling mistake in the main function by accidentally using vooid instead of void .
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Is errno thread-safe?
...l
errno is defined by including the
header , as specified by the
C Standard ... For each thread of a
process, the value of errno shall not
be affected by function calls or
assignments to errno by other threads.
Also see http://linux.die.net/man/3/errno
errno is thread-local; settin...
How do I lock the orientation to portrait mode in a iPhone Web Application?
I'm building a iPhone Web Application and want to lock the orientation to portrait mode. is this possible? Are there any web-kit extensions to do this?
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Google Play on Android 4.0 emulator
How can I install the Google Play .apk onto my Android 4.0 emulator?
8 Answers
8
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