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ALTER TABLE without locking the table?
When doing an ALTER TABLE statement in MySQL, the whole table is read-locked (allowing concurrent reads, but prohibiting concurrent writes) for the duration of the statement. If it's a big table, INSERT or UPDATE statements could be blocked for a looooong time. Is there a way to do a "hot alter", li...
Why are elementwise additions much faster in separate loops than in a combined loop?
Suppose a1 , b1 , c1 , and d1 point to heap memory and my numerical code has the following core loop.
10 Answers
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Tags for Emacs: Relationship between etags, ebrowse, cscope, GNU Global and exuberant ctags
I work on C++ projects, and I went through Alex Ott's guide to CEDET and other threads about tags in StackOverflow, but I am still confused about how Emacs interfaces with these different tag systems to facilitate autocompletion, the looking up of definitions, navigation of source code base or the...
What is the difference between aggregation, composition and dependency? [duplicate]
What is the difference between aggregation, composition and dependency?
7 Answers
7
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What are the differences between a HashMap and a Hashtable in Java?
What are the differences between a HashMap and a Hashtable in Java?
35 Answers
35
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Didn't Java once have a Pair class? [duplicate]
Am I remembering incorrectly, or did Java, once upon a time, provide a Pair class as part of its API?
10 Answers
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When is null or undefined used in JavaScript? [duplicate]
I am really confused as to when JavaScript returns null or undefined . Also different browsers seem to be returning these differently.
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How to determine equality for two JavaScript objects?
A strict equality operator will tell you if two object types are equal. However, is there a way to tell if two objects are equal, much like the hash code value in Java?
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Why not be dependently typed?
I have seen several sources echo the opinion that "Haskell is gradually becoming a dependently-typed language". The implication seems to be that with more and more language extensions, Haskell is drifting in that general direction, but isn't there yet.
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Best Timer for using in a Windows service
I need to create some windows service which will execute every N period of time.
The question is:
Which timer control should I use: System.Timers.Timer or System.Threading.Timer one? Does it influence on something?
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