Aleksey Demakov created IGNITE-19666:
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             Summary: Remove null map in Binary Tuple format
                 Key: IGNITE-19666
                 URL: https://issues.apache.org/jira/browse/IGNITE-19666
             Project: Ignite
          Issue Type: Improvement
            Reporter: Aleksey Demakov


To move towards single-pass in-place construction of binary tuples the biggest 
obstacle is presence of the null map.

It is proposed to encode null values as a single-byte special value (null mark) 
in-line with regular values. It is required to escape regular values that have 
the same bit pattern as the null mark so the null mark needs to be relatively 
rare. The value of 0x80 seems a good one.

By the way, this would greatly simplify making tuples from other tuples. E.g. 
if we need to copy values for a column range [3, 7] from one tuple to another 
tuple, we could copy values almost blindly with single memory copy. No need for 
any bit magic anymore.



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