====== REGEXP_LIKE ======

===== 정의 =====
  - 오라클 정규표현식의 하나.
===== 이메일 형식 체크 =====
  - 이메일 형식 체크(Validate)이 맞는지 확인하는 쿼리이다. <code>
select email 
from member 
where regexp_like(email,'[^ ]+@[^.][^ ]+\..[^ ]+');
</code>
  - 이메일 형식체크에 quotes 를 포함하여 아래의 구문을 따른다. <code>
'[a-zA-Z0-9._%-]+@[a-zA-Z0-9._%-]+\.[a-zA-Z]{2,4}' 
</code> \\ http://stackoverflow.com/questions/787167/validation-on-email-postcode-fields-in-sql-oracle

===== 날짜형식 체크 =====
  - 날짜형식 체크 <code>
ALTER SESSION SET NLS_LANGUAGE='AMERICAN';
with t as (
  select '01-02-2007' str from dual union all
  select '7-8-2007'   str from dual union all
  select '2007/03/28' str from dual union all
  select '10-MAY-07'  str from dual
)
select str
  , to_date(str, case when regexp_like(str,'[0-9]{1,2}-[0-9]{1,2}-[0-9]{4}')
                           then 'dd-mm-yyyy'
                      when regexp_like(str,'[0-9]{4}/[0-9]{1,2}/[0-9]{1,2}')
                           then 'yyyy/mm/dd'
                      when regexp_like(str,'[0-9]{2}-[A-Z]{3}-[0-9]{2}')
                           then 'dd-mon-yy'
                 end) as date1
from t;
</code> \\ ORA-01843: not a valid month 가 나올경우 NLS_LANG 을 확인해 본다. \\ <code>
with t as (
  select '01-02-2007' str from dual union all
  select '7-8-2007'   str from dual union all
  select '2007/03/28' str from dual union all
  select '10-MAY-07'  str from dual
)
select str
  , to_date(str, case when regexp_like(str,'[0-9]{1,2}-[0-9]{1,2}-[0-9]{4}')
                           then 'dd-mm-yyyy'
                      when regexp_like(str,'[0-9]{4}/[0-9]{1,2}/[0-9]{1,2}')
                           then 'yyyy/mm/dd'
                      when regexp_like(str,'[0-9]{2}-[A-Z]{3}-[0-9]{2}')
                           then 'dd-mon-yy'
                 end,'NLS_DATE_LANGUAGE=AMERICAN') as date1
from t;
</code>