dba_tab_col_statistics
根据yuang hong的文章,9i中无上述视图,不过可以从dba_tab_col_statistics 视图的代码中得知可用下面的语句查看　　9i的histogram type (注：10g与9i中histogram无大的变化).

注意xxx_tab_col_statistics中的column statistics和histogram infomation均取自ALL_TAB_COL_STATISTICS provides column statistics and histogram information
extracted from "ALL_TAB_COLUMNS" on page 2-124.
所以,<>的目录中无

select case when nvl(h.row_cnt,0) = 0 then 'NONE'
     when (h.bucket_cnt > 255
           or
           (h.bucket_cnt > h.distcnt and h.row_cnt = h.distcnt
            and h.density*h.bucket_cnt*2 <= 1))
         then 'FREQUENCY'
     else 'HEIGHT BALANCED'
end
from sys.hist_head$ h
where obj# = &object_id_for_the_table;

ITPub博客

about histogram(2)

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