select ts.tbcxsx into param_timeLimit from winf_sv_ex_hybs_tbcxsq ts
  where ts.sblsh=:new.sblsh and ts.xh=:new.xh;

  如果未找到任何记录，后面加一句

  Exception when no_data_found then  
  param_timeLimit := 0;   即可；

oracle中触发器报错：未找到数据