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How important is the order of columns in indexes?
I've heard that you should put columns that will be the most selective at the beginning of the index declaration. Example:
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How do you specify a byte literal in Java?
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You cannot. A basic numeric constant is considered an integer (or long if followed by a "L"), so you must explicitly downcast it to a byte to pass it as a parameter. As far as I know there is no shortcut.
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Immutable vs Mutable types
I'm confused on what an immutable type is. I know the float object is considered to be immutable, with this type of example from my book:
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Git undo changes in some files [duplicate]
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There are three basic ways to do this depending on what you have done with the changes to the file A. If you have not yet added the changes to the index or committed them, then you just want to use the checkout command - this will change the...
How Many Seconds Between Two Dates?
...ime() - t2.getTime();
var Seconds_from_T1_to_T2 = dif / 1000;
var Seconds_Between_Dates = Math.abs(Seconds_from_T1_to_T2);
A handy source for future reference is the MDN site
Alternatively, if your dates come in a format javascript can parse
var dif = Date.parse(MM + " " + DD + ", " + YYYY) - D...
How do you append an int to a string in C++? [duplicate]
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F14
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answered Sep 25 '13 at 6:39
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What is the difference between precision and scale?
What is the difference between precision and scale in Oracle? In tutorials they usually leave scale empty and set precision to 6 when creating a primary key.
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Passing multiple error classes to ruby's rescue clause in a DRY fashion
I have some code that needs to rescue multiple types of exceptions in ruby:
3 Answers
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Why do you need to invoke an anonymous function on the same line?
I was reading some posts about closures and saw this everywhere, but there is no clear explanation how it works - everytime I was just told to use it...:
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Calculate a Running Total in SQL Server
Imagine the following table (called TestTable ):
15 Answers
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