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From Dyre.Tjeldv...@Sun.COM
Subject Bitsets in IndexRowToBaseRowResultSet
Date Sun, 10 Dec 2006 14:30:39 GMT

It seems to me that the constructor for IndexRowToBaseRowResultSet
takes a bitset describing the columns coming from the heap and a
bitset describing the columns coming from the index. But in every
IndexRowToBaseRowResultSet one also has to compute _all_ referenced
columns (union of heap and index bitsets), and frequently also those
columns _only_ coming from the heap (set difference between heap and
index).

But the value of these "set products" seem _only_ to depend on objects
that are fixed at compile time (in IndexToBaseRowNode), so would it
not be cleaner (and possibly more efficient) to compute these products
in IndexToBaseRowNode as well, and just refer to them when creating
IndexRowToBaseRowResultSets? Or would this have some undesirable side
effect that I'm not aware of?

-- 
dt

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