在数据库中存在着子父级的列,比如:系列分为风,雨,雅典,而风又有子级:F01、F02等。如果统计系列为风的数量时,则F01、F02也应该包括在内,SQL语句怎样写????
select * from sale where series in (select series from base where series like '%风%') or series like '%风%'
select * from sale where series in (select series from base where series like '%风%') or series like '%风%'
如系列结构表XLB
父系列FS,儿系列SS
则你统计如下:
select count(*) from sale where series in
(select distinct SS from XLB
connect by Prior SS=FS
start with FS='风')
or series = '风';上面的方法在Oracle中可以,其它数据库可以类似写出.
id pra_id mc
1 -1 风
2 1 F01
3 1 F02