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What is hashCode used for? Is it unique?
...r is based on the
System.Collections.IEqualityComparer interface.
Basically, hash codes exist to make hashtables possible.
Two equal objects are guaranteed to have equal hashcodes.
Two unequal objects are not guaranteed to have unequal hashcodes (that's called a collision).
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Why do you create a View in a database?
...joining several tables, or has complex logic or calculations, you can code all that logic into a view, then select from the view just like you would a table.
2. Views can be used as a security mechanism
A view can select certain columns and/or rows from a table (or tables), and permissions set on ...
HTML5 doctype putting IE9 into quirks mode?
...bhishek: meta elements need not be explicitly closed in HTML5 (and historically against older HTML specs closing it would in fact be invalid).
– reisio
May 23 '12 at 19:19
4
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LINQ: Not Any vs All Don't
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Implementation of All according to ILSpy (as in I actually went and looked, rather than the "well, that method works a bit like ..." I might do if we were discussing the theory rather than the impact).
public static bool All<TSource>(th...
How to get and set the current web page scroll position?
... This answer is not accurate as the scrollTop property doesn't work on all browsers. Check window.pageXOffset and window.pageYOffset for better results.
– gyo
Nov 26 '15 at 10:57
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Where does Xcode 4 store Scheme Data?
... use Xcode 4, and I'm trying to find the file in a project where it stores all of a project's Schemes. I figured they would be stored in a file in the xcodeproj directory somewhere, but for the life of me I can't find which one.
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Erlang's 99.9999999% (nine nines) reliability
...ntime, the author can state "nine nines reliability" for AXD301 (which was all he ever said, avoiding specifics). It doesn't necessarily mean Erlang is the only cause of such high reliability.
EDIT: In fact, "20 years" itself seems like a misinterpretation. Joe mentions a figure of 20 years in the s...
what is the difference between GROUP BY and ORDER BY in sql
... returned.
GROUP BY will aggregate records by the specified columns which allows you to perform aggregation functions on non-grouped columns (such as SUM, COUNT, AVG, etc).
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How to pause for specific amount of time? (Excel/VBA)
...lare PtrSafe Sub Sleep Lib "kernel32" (ByVal dwMilliseconds As LongPtr)
Call it in your macro like so:
Sub Macro1()
'
' Macro1 Macro
'
Do
Calculate
Sleep (1000) ' delay 1 second
Loop
End Sub
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MySQL Results as comma separated list
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The intent is fine and MySQL will allow this, but be careful (generally) with your use of GROUP BY. The items in the select list need to be valid aggregates in the context of the GROUP BY clause. In this case, p.name is not strictly valid. Any database con...