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DA Morgan wrote on 04.03.2006 00:43:
>> I would have loved to do that. This increases my storage requirements >> by 5 times. >>> From 5 Tera bytes to 25 Terabytes and makes my queries more complex .
Of course, bytes are bytes. But you will need more of them if you move to a vertical structure. With the name/value approach you'll store the name each time as well, something you don't do with the 900 columns (because the "names" are stored in the repository).
Assuming we have 1 byte in each column (=value) then one row will use 900 bytes (disregarding management overhead). If I store this in a name/value pair table, I wind up with 900 rows, each row holding the (original) 1 byte data, and at least two bytes identifying the name (because I need at least two byte to store 900 distinct values), so I'll have 1800 additional bytes to store my names. Which makes a total of 2700 bytes vs. 900 for the horizontal solution.
But maybe I overlooked something.
Thomas Received on Fri Mar 03 2006 - 18:10:15 CST