• Igor Babaev's avatar
    BNLH algorithm always used a full table scan over the joined table · 272e5e62
    Igor Babaev authored
    even in the cases when there existed range/index-merge scans that
    were cheaper than the full table scan.
    This was a defect/bug of the implementation of mwl #128. 
    Now hash join can work not only with full table scan of the joined
    table, but also with full index scan, range and index-merge scans.
    Accordingly, in the cases when hash join is used the column 'type'
    in the EXPLAINs can contain now 'hash_ALL', 'hash_index', 'hash_range'
    and 'hash_index_merge'. If hash join is coupled with a range/index_merge
    scan then the columns 'key' and 'key_len' contain info not only on
    the used hash index, but also on the indexes used for the scan.   
    272e5e62
join_outer_jcl6.result 53 KB