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Storing time-series data, relational or non?

... description, the actual PK is (Device, Metric, DateTime). (Please don't call it TimeStamp, that means something else, but that is a minor issue.) The uniqueness of the row is identified by: (Device, Metric, DateTime) The Id column does nothing, it is totally and completely redundant. A...
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How to write log base(2) in c/c++

...mpiler doesn't know that log10 will return the same value every time. For all the compiler knows, log10(2) could return different values on successive calls. – abelenky Jun 17 '10 at 21:24 ...
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Where to place AutoMapper.CreateMaps?

...t of overhead. I'm not too sure how to design my application to put these calls in just 1 place. 10 Answers ...
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Django 1.7 throws django.core.exceptions.AppRegistryNotReady: Models aren't loaded yet

...1.4, not in 1.5, and not in 1.7. If you had it in there, it was added manually by someone - it is not added by django-admin startproject. – wim Oct 11 '16 at 16:54 ...
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Why does the MongoDB Java driver use a random number generator in a conditional?

...k && Math.random() <= 0.1) return res; The commit that originally introduced this logic had if (_ok == true) { _logger.log( Level.WARNING , "Server seen down: " + _addr, e ); } else if (Math.random() < 0.1) { _logger.log( Level.WARNING , "Server seen down: " + _addr ); } —a...
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Iterate over the lines of a string

...())' 10000 loops, best of 3: 61.5 usec per loop Note we need the list() call to ensure the iterators are traversed, not just built. IOW, the naive implementation is so much faster it isn't even funny: 6 times faster than my attempt with find calls, which in turn is 4 times faster than a lower-lev...
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Batch Renaming of Files in a Directory

...name(r'c:\temp\xx', r'*.doc', r'new(%s)') The above example will convert all *.doc files in c:\temp\xx dir to new(%s).doc, where %s is the previous base name of the file (without extension). share | ...
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Localization of DisplayNameAttribute

... I looked all over before finding this page... this is such a life saver. Thanks! Works good on MVC5 for me. – Kris Apr 20 '18 at 14:42 ...
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Difference between \w and \b regular expression meta characters

...chor like the caret and the dollar sign. It matches at a position that is called a "word boundary". This match is zero-length. There are three different positions that qualify as word boundaries: Before the first character in the string, if the first character is a word character. After the last ...
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ASP.NET MVC - Attaching an entity of type 'MODELNAME' failed because another entity of the same type

...'Modified'. Before changing the state, the state is set to 'Detached' but calling Attach() does throw the same error. I'm using EF6. ...