帮我解析下这段SQL语句好吗？

[mfzhao]

select distinct fb_mamodel from tblb_machine where fb_macode in(select distinct fb_macode from tblb_matoba where fbatterycode='$fbatterycode') and fclasscode='1' and fb_mabrand='$fb_babrand'"

[zalvsa]

查询唯一的fb_mamodel，该值满足条件
1）值的范围在是在tblb_matoba表里并且 fbatterycode='$fbatterycode'（子查询）
2） fclasscode='1' and fb_mabrand='$fb_babrand'"

[zysoft17]

select distinct fb_mamodel from tblb_machine where fb_macode in(select distinct fb_macode from tblb_matoba where fbatterycode='$fbatterycode') and fclasscode='1' and fb_mabrand='$fb_babrand'"

distinct : 使记录不重复

查询 fb_macode 等于子查询 (select distinct fb_macode from tblb_matoba where fbatterycode='$fbatterycode')
并且满足 fclasscode='1' and fb_mabrand='$fb_babrand'

[mfzhao]

谢谢

"select distinct * from tblad_machine where fmabrand='$mabrand' and fmacode in (select distinct fmacode from tblmatoad where fadcode in (select distinct fadcode from tblnewadapters where ftype='AC')) order by fmabrand"

这个列复杂