예를 들어 날짜를 계산하는데 이전 날짜를 가져와서 어떠한 날짜로 치완하고 싶을 때...이전 날짜를 어떻게 가져올 수 있을까?? 오라클에서는 LAG, LEAD 함수를 사용한다. LAG 함수 사용SELECTHIST_SEQ, EQUIP_NO, CHCK_DT, NVL(CHCK_DT, LAG(CHCK_DT) OVER (PARTITION BY EQUIP_NO ORDER BY HIST_SEQ)) BEFOR_CHCK_DT, TRET_ST_FG,ROW_NUMBER() OVER(PARTITION BY EQUIP_NO ORDER BY HIST_SEQ DESC) RN FROM EQPM_CHECK_HIST LEAD 함수SELECTHIST_SEQ, EQUIP_NO, CHCK_DT, NVL(CHCK_DT, LEAD(CHCK_DT)..

SELECT *FROM DEPT_INFOWHERE CONNECT_BY_ISLEAF = 1 AND CONNECT_BY_ISCYCLE = 0START WITH PARNTS_DEPT_CD = '00000000'CONNECT BY NOCYCLE PRIOR DEPT_CD = PARNTS_DEPT_CD;

UPDATE TABLE1 T1 SET (NAME, DESC) = ( SELECT T2.NAME, T2.DESC FROM TABLE2 T2 WHERE T1.ID = T2.ID )WHERE EXISTS ( SELECT 1 FROM TABLE2 T2 WHERE T1.ID = T2.ID );

1. 테이블 목록조회SELECT *FROM all_all_tables; SELECT *FROM dba_tables; SELECT *FROM ALL_OBJECTSWHERE OBJECT_TYPE = 'TABLE' -- 접속한 계정의 테이블 목록보기SELECT *FROM tabs; SELECT *FROM USER_OBJECTS WHERE OBJECT_TYPE = 'TABLE'; SELECT *FROM USER_TABLES; -- 테이블 코멘트 보기SELECT *FROM ALL_TAB_COMMENTSWHERE TABLE_NAME = '테이블명' SELECT *FROM USER_TAB_COMMENTS; 2. 컬럼 목록조회SELECT *FROM COLS;WHERE TABLE_NAME = '테이블명'; SELECT ..

select b.machine "hostname", b.username "username", b.osuser "OS User", b.program "Program", a.tablespace_name "TableSpace", row_wait_file# "File Number", row_wait_block# "Block Number", c.owner, c.segment_name, c.segment_type from dba_data_files a, v$session b, dba_extents c where b.row_wait_file# = a.file_id and c.file_id = row_wait_file# and row_wait_block# between c.block_id and c.block_id +..