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From Jonathan Ellis <>
Subject Re: Reason for not allowing null values for in Column
Date Mon, 08 Mar 2010 17:10:18 GMT
On Mon, Mar 8, 2010 at 11:07 AM, Erik Holstad <> wrote:
> Why is it that null column values are not allowed?

It's semantically unnecessary and potentially harmful at an
implementation level.  (Many java Map implementations can't
distinguish between a null key and a key that is not present.)

> What is the reason for using a ConcurrentSkipListMap<byte[], IColumn> for
> columns_ in ColumnFamily
> compared to using the set version and use the comparator to sort on the name
> field in IColumn?


> For the call get_range_slice() you get all the rows returned even though
> they might have been deleted,

Yes, that is the point.

> is it really that expensive to check if the list is empty before returning
> that row

Yes, because you have to check the entire row, which may be much
larger than the given predicate.


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