delphi的adoquery中使用sql case语句

DataModule2.ADOQuery1_630.sql.clear;

DataModule2.ADOQuery1_630.sql.Add('SELECT * FROM table');

DataModule2.ADOQuery1_630.sql.Add('WHERE STATUT in(:dd,:df) and TYPE_QUIT=:l');

DataModule2.ADOQuery1_630.sql.Add('GROUP BY STATUT');

DataModule2.ADOQuery1_630.Parameters.ParamByName('dd').Value:=pm;

DataModule2.ADOQuery1_630.Parameters.ParamByName('df').Value:=pp;

DataModule2.ADOQuery1_630.Parameters.ParamByName('l').Value:=typeQ;

DataModule2.ADOQuery1_630.prepared := true;

DataModule2.ADOQuery1_630.open;