MySQL The basic idea of removing duplicate query SQL statement

SELECTR.*  fromTrans_flow R, (SELECTOrder_no,MAX(Status_time) asStatus_time fromTrans_flowGROUP  byorder_no) SWHERER.order_no=S.order_no andR.status_time=S.status_timeORDER  byR.status_timeDESC SELECTA.order_no,a.mem_no,c.card_no,c.card_holder,c.bank_name,c.branch_bank_name,a.flag, A.income_type_txt,a.amt, A.create_time fromAccount_log aJOIN(SELECTB.*,MAX(ID) fromAccount BGROUP  byb.mem_no) C onDate_add (A.create_time, INTERVAL7  Day)<Now () andA. ' Mem_no '=C.mem_noORDER  bya.IDdesc   

Workaround:
The structure is as follows:
type name guest       date
1   aa        sa           20131101
1    bb      dsf           20131102
1   aa      wew         20131103
I want to group by name, in descending order of date, and I want the result as follows:
type name guest   date
1   aa        wew     20131103
1   bb       DSF        20131102

select r.* from tab  R, ( Select Name, max (date) From the tab group by name) S
where R.name=s.name and R.date=s . Date
order by r.date desc

MySQL Remove duplicate query SQL statement basic idea