如何判断字串里逗号的个数？

Question

SQL> select lengthb('ad,wef,wert,erg')-lengthb(replace('ad,wef,wert,erg',',','')) from dual;LENGTHB('AD,WEF,WERT,ERG')-LENGTHB(REPLACE('AD,WEF,WERT,ERG',',',''))
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                                                                    3已用时间:  00: 00: 00.20
SQL>

Answer 1

楼上的做法真妙！再次钦佩bzszp(SongZip)...

Answer 2

create or replace function r_num(
     i_string     varchar2) return number is
     i      integer;
begin
    i:=1;
    while instr(i_string, ',', 1, i)>0  loop
        i:=i+1;
    end loop;
    i:=i-1;
    return i;
end;