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From Jérôme Mainaud <jer...@mainaud.com>
Subject Partition size estimation formula in 3.0
Date Mon, 19 Sep 2016 13:12:32 GMT
Hello,

Until 3.0, we had a nice formula to estimate partition size :

      sizeof(partition keys)
    + sizeof(static columns)
    + countof(rows) * sizeof(regular columns)
    + countof(rows) * countof(regular columns) * sizeof(clustering columns)
    + 8 * count(values in partition)

With the 3.0 storage engine, the size is supposed to be smaller.
And I'm looking for the new formula.

I reckon the formula to become :

      sizeof(partition keys)
    + sizeof(static columns)
    + countof(rows) * sizeof(regular columns)
    + countof(rows) * sizeof(clustering columns)
    + 8 * count(values in partition)

That is the clustering column values are no more repeated for each regular
column in the row.

Could anyone confirm me that new formula or am I missing something ?

Thank you,

-- 
Jérôme Mainaud
jerome@mainaud.com

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