fxz0

  select * from table(p_split('1,2,3'),',');

  create or replace type type_split is table of varchar2(4000);

  create or replace function p_split(p_string in varchar2, p_delimiter in varchar2)
    return type_split
    pipelined
  as
    v_length number:=length(p_string);
    v_start number:=1;
    v_index number;
  begin
    while(v_start<=v_length)
    loop
      v_index:=instr(p_string,p_delimiter,v_start);
      if v_index = 0
      then
        pipe row(substr(p_string,v_start));
        v_start:=v_length + 1;
      else
        pipe row(substr(p_string, v_start, v_index - v_start));
        v_start:=v_index + 1;
      end if;
    end loop;
    return;
  end p_split;

select listagg(字段名,',') within group (order by 字段名) from 表名 where 條件

case when 條件1 then 結(jié)果1
     when 條件2 then 結(jié)果2
     else 結(jié)果3
end;

merge into 表
using (表|視圖|子查詢等)
on (條件)
when match then
 update set 字段=值  
when no match then
 insert (字段...) values (值...)