mysql动态sql问题
DELIMITER $$;

DROP PROCEDURE IF EXISTS `web_oa_database`.`search_problem`$$

CREATE PROCEDURE `web_oa_database`.`search_problem` (
in p_id int,
in tm1 varchar(50),
in tm2 varchar(50),
in k_ft varchar(100),
in p_tp varchar(50),
in k_pb varchar(200),
in p_gd varchar(20),
in p_ic varchar(200),
in s_t varchar(30)
)
BEGIN
  declare str varchar(2000);
  set str='';
  if p_id<>0 then
  set str=concat(' where data083.pid=',p_id);
  end if;
  if tm1<>'' then
  if str='' then
  set str=concat(' where data083.ftm>=',tm1,' and data083.ftm<=',tm2);
  else
  set str=concat(str,' and data083.ftm>=',tm1,' and data083.ftm<=',tm2);
  end if;
  end if;
  if k_ft<>'' then
  if str='' then
  set str=concat(' where data083.kft like',' %',k_ft,'%');
  else
  set str=concat(str,' and data083.kft like',' %',k_ft,'%');
  end if;
  end if;
  if p_tp<>'' then
  if str='' then
  set str=concat(' where data083.ptp=',p_tp);
  else
  set str=concat(str,' and data083.ptp=',p_tp);
  end if;
  end if;
  if k_pb<>'' then
  if str='' then
  set str=concat(' where data083.kpb like', ' %',k_pb,'%');
  else
  set str=concat(str,' and data083.kpb like',' %',k_pb,'%');
  end if;
  end if;
  if p_gd<>'' then
  if str='' then
  set str=concat(' where data083.pgd=',p_gd);
  else
  set str=concat(str,' and data083.pgd=',p_gd);
  end if;
  end if;
  if p_ic<>'' then
  if str='' then
  set str=concat(' where data083.pic like',' %',p_ic,'%');
  else
  set str=concat(str,' and data083.pic like',' %',p_ic,'%');
  end if;
  end if;
  if s_t<>'' then
  if str='' then
  set str=concat(' where data083.st=',s_t);
  else
  set str=concat(str,' and data083.st=',s_t);
  end if;
  end if;
  set str=concat('select * from data083 ',str);
  
  SET @sql=str;  

  PREPARE stmt FROM @sql;  

  EXECUTE stmt;  

  DEALLOCATE PREPARE stmt;  

END$$

DELIMITER ;$$

//错误提示很明了：DBAccess.execQuery()Unknown column '??“???è??è??' in 'where clause'，但是检查了半天，没有发现表列名有误。就怀疑是sql语句拼接出了问题，一时间也找不出来，望高手能看下，指点下错误，不胜感激，谢谢！

------解决方案--------------------

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