摘要：
first_ value（block_id）over（PARTITIONBYDOI，last_value（relative_no）over（PARTITIONBYDOI），last_vvalue（blocks_id+blocks-1）over（partitionBYDO，SUM（blocks）over）（ORDERBYDATA_OBJECT_id，
通过如下sql获取rowid切分范围
SELECT rownum || ', ' || ' rowid between ' || chr(39) || dbms_rowid.rowid_create(1, DOI, lo_fno, lo_block, 0) || chr(39) || ' and ' || chr(39) || dbms_rowid.rowid_create(1, DOI, hi_fno, hi_block, 1000000) || chr(39) data FROM (SELECT DISTINCT DOI, grp, first_value(relative_fno) over(PARTITION BY DOI, grp ORDER BY relative_fno, block_id rows BETWEEN unbounded preceding AND unbounded following) lo_fno, first_value(block_id) over(PARTITION BY DOI, grp ORDER BY relative_fno, block_id rows BETWEEN unbounded preceding AND unbounded following) lo_block, last_value(relative_fno) over(PARTITION BY DOI, grp ORDER BY relative_fno, block_id rows BETWEEN unbounded preceding AND unbounded following) hi_fno, last_value(block_id + blocks - 1) over(PARTITION BY DOI, grp ORDER BY relative_fno, block_id rows BETWEEN unbounded preceding AND unbounded following) hi_block, SUM(blocks) over(PARTITION BY DOI, grp) sum_blocks, SUBOBJECT_NAME FROM (SELECT obj.OBJECT_ID, obj.SUBOBJECT_NAME, obj.DATA_OBJECT_ID AS DOI, ext.relative_fno, ext.block_id, SUM(blocks) over() SUM, SUM(blocks) over(ORDER BY DATA_OBJECT_ID, relative_fno, block_id) - 0.01 sum_fno, TRUNC((SUM(blocks) over(ORDER BY DATA_OBJECT_ID, relative_fno, block_id) - 0.01) / (SUM(blocks) over() / &cnt)) grp, ext.blocks FROM dba_extents ext, dba_objects obj WHERE ext.segment_name = '&object_name' AND ext.owner = '&owner' AND obj.owner = ext.owner AND obj.object_name = ext.segment_name AND obj.DATA_OBJECT_ID IS NOT NULL ORDER BY DATA_OBJECT_ID, relative_fno, block_id) ORDER BY DOI, grp);