Oracle to PostgreSQL 쿼리 변환

Oracle 쿼리를 PostgreSQL 쿼리로 변경 할때 수정 해야 할 부분입니다. 

테이블 이관은 찾아보면 무료로 사용 할 수 있는게 몇가지 있습니다. 적당한 것으로 하시면 될거 같습니다.

Oracle	PostgreSQL	비고
select sysdate FROM DUAL	select now()
sysdate	now()
ROWNUM	(ROW_NUMBER() OVER())	select 절
WHERE ROWNUM =	LIMIT	where
NVL	coalesce
left outer join (+)	(left table) left outer join (Right table) on left.col = right.col
right outer join (+)	(left table) right outer join (Right table) on left.col = right.col
inner join	(left table) inner join (Right table) on left.col = right.col
connect by	WITH RECURSIVE RC AS ( select Cast(R.MENU_ID as TEXT) as SYS_MENU_PATH, cast(R.MENU_NM as TEXT) as PGM_MENU_PATH, 1 as level,R.MENU_ID, R.MENU_NM, R.UPPER_MENU_ID FROM EO_MENU R WHERE R.UPPER_MENU_ID = 206 UNION all select Cast((RC.SYS_MENU_PATH ||';'|| R.MENU_ID) as TEXT) as SYS_MENU_PATH , cast(RC.PGM_MENU_PATH ||'>'|| R.MENU_NM as text) as PGM_MENU_PATH, RC.level +1 as level, R.MENU_ID,R.MENU_NM,R.UPPER_MENU_ID from EO_MENU R join RC on RC.MENU_ID = R.UPPER_MENU_ID ) (case when (select distinct RC.MENU_ID from RC leaf where leaf.UPPER_MENU_ID=RC.MENU_ID) is null then 1 else 0 end) as is_leaf	계층구조 데이터
to_number	::numeric to_number('123','999') , to_number('1234','99999999') cast(xxxx as text)	숫자변환
decode	case when then else end
ADD_MONTHS(sysdate),-1)	now() + interval '-1 month'
SEQ_EO_COUPONTYPE_00.NEXTVAL	NEXTVAL('SEQ_EO_COUPONTYPE_00')	Sequence
MERGE INTO COMTNAUTHORINFO USING DUAL ON (AUTHOR_CODE = 'ROL_TEST1')     WHEN MATCHED THEN UPDATE SET     AUTHOR_NM = '테스트권한'     ,AUTHOR_DC = '테스트권한'     ,AUTHOR_CREAT_DE = '2020-09-01'     WHEN NOT MATCHED THEN INSERT     (AUTHOR_CODE,         AUTHOR_NM,         AUTHOR_DC,         AUTHOR_CREAT_DE)     VALUES ('ROL_TEST',  '테스트권한1',  '테스트권한1',     SYSDATE);	WITH UPSERT AS(     UPDATE comtnauthorinfo SET         author_nm = '테스트권한'         ,author_dc = '테스트권한'         ,author_creat_de = '2020-09-01'     WHERE author_code = 'ROL_TEST'  RETURNING * ) INSERT INTO comtnauthorinfo (author_code, author_nm, author_dc, author_creat_de) SELECT 'ROL_TEST',        '테스트권한1',        '테스트권한1',        CURRENT_TIMESTAMP WHERE NOT EXISTS(SELECT  * FROM UPSERT);	merge into