select replace('Аскаров,Аскат', ',', ' ') from dual;

  1  with Person(ID, FIO) as (
  2  select 100,'Иванов И.И.' from dual union all
  3  select 200,'Иванова А.П.' from dual union all
  4  select 300,'Петров А.П.' from dual union all
  5  select 400,'Петрова А.А.' from dual union all
  6  select 500,'Сидорова А.Ф.' from dual union all
  7  select 600,'Сидорова А.К.' from dual)
  8  ,Pairs(id,IDG, IDM, WEDDING_DATE) as (
  9  select 1,  100,    400,to_date('01-02-98') from dual union all
 10  select 2,  300,    400,to_date('02-10-00') from dual union all
 11  select 3,  500,    600,to_date('02-10-00') from dual )
 12  select * from person
 13* where instr(','||'Петров А.П.,Сидорова А.К.'||',',','||fio||',')>0
SQL> /

        ID FIO
---------- -------------
       300 Петров А.П.
       600 Сидорова А.К.