GitHub user jianqiao opened a pull request:

    Fix a bug with min/max aggregation.

    This PR fixes the bug with min/max aggregation (that produces incorrect 
results) when the aggregated column is stored with **leading-zero-truncation 
    The bug happens because the untyped value (i.e. a `const void *` pointer) 
obtained from the leading-zero-truncation compressed column's corresponding 
`ValueAccessor` is [the address of a temporary 
 -- i.e. the value pointer becomes invalid when the next `accessor->next()` 
gets called. [Keeping the value 
 across [multiple iterations 
 accessor->next() causes the problem.
    The fix is to copy the value pointer's underlying value to a local variable 
(so that the value remains valid across iterations of accessor->next()).

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    This closes #277
commit f3b792bf532aad41724b91cf88c97fcfbbdc1ea9
Author: Jianqiao Zhu <>
Date:   2017-08-02T20:47:30Z

    Fix the bug with min/max aggregation.


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