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What are the disadvantages of using persistent connection in PDO
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I hope I had read this answer before running SELECT orders.* FROM orders LEFT JOIN items USING(item_id)
– Ast Derek
Jul 26 '10 at 18:09
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Is there a better way to express nested namespaces in C++ within the header
...ESPACE_BEGIN(Foo, Bar, Baz)
class X { };
NAMESPACE_END(Baz, Bar, Foo) // order doesn't matter, NAMESPACE_END(a, b, c) would work equally well
Foo::Bar::Baz::X x;
For nesting deeper than three levels you would have to add helper macros up to the desired count.
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Declaring variables inside or outside of a loop
...f having to go all over your entire code base and tweak and hack things in order to squeeze clock cycles here and there.
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When do I need to use a semicolon vs a slash in Oracle SQL?
...e 1:
ORA-00942: table or view does not exist
The / is mainly required in order to run statements that have embedded ; like a CREATE PROCEDURE statement.
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How to determine if binary tree is balanced?
...ion cost. You spend a lot of time doing unnecessary tree rearrangements in order to attain a level of balance that in practice makes little difference. Who cares if sometimes it takes forty branches to get to the farthest leaf in a million-node imperfectly-balanced tree when it could in theory take ...
When to use inline function and when not to use it?
...f the library call the old implementation
when developing a library, in order to make a class extensible in the future you should:
add non-inline virtual destructor even if the body is empty
make all constructors non-inline
write non-inline implementations of the copy constructor and assignment...
Does Java 8 provide a good way to repeat a value or function?
...wenting To anyone with experience in FP, code which revolves around higher-order functions is a pure win. To anyone without that experience, it's time to upgrade your skills---or risk being left behind in the dust.
– Marko Topolnik
Aug 30 '13 at 12:14
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Why should eval be avoided in Bash, and what should I use instead?
...>&3 2>&1 # Redirect stdout to &3, and stderr to stdout: order matters
command <&3 >&4 # Input and output!
Variable indirection
Scenario:
VAR='1 2 3'
REF=VAR
Bad:
eval "echo \"\$$REF\""
Why? If REF contains a double quote, this will break and open the code...
Is there any way to do a “Replace Or Insert” using web.config transformation?
I'm using web.config transformation as described in the below post in order to generate configs for different environments.
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How can I get the external SD card path for Android 4.0+?
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In order to retrieve all the External Storages (whether they are SD cards or internal non-removable storages), you can use the following code:
final String state = Environment.getExternalStorageState();
if ( Environment.MEDIA_...