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Showing posts from February 26, 2012

what does "granularity" mean when speaking of database

I'm kinda confused what exactly does "granularity" or "grain"means in database world. So I just understand that this means "it's a measure of level of details of your data in a database". It's how you could get a minimal grains of your data or how you could get a detailed information of your data that's make sense. From Wikipedia, it means, Data granularity The  granularity  of data refers to the fineness with which data fields are sub-divided. For example, a postal address can be recorded, with  low granularity , as a single field: address = 200 2nd Ave. South #358, St. Petersburg, FL 33701-4313 USA or with  high granularity , as multiple fields: street address = 200 2nd Ave. South #358 city = St. Petersburg postal code = FL 33701-4313 country = USA or even higher granularity: street = 2nd Ave. South address number = 200 suite/apartment number = #358 city = St. Petersburg state = FL postal-code = 33701 postal-code-add-o

Product Rule, Chain Rule and then Factoring

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I found this video is really cool and easy to understand. Please have your attention during factoring because the author of the video did a long factorization of polynomials to make it shorten for the derivatives. and this example also is quite easy,

Finding Partial Derivatives

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In this video, I find this tutorial very easy for me to understand what is a partial derivative. It has good examples including a chain rule.