ORACLE 인덱스
DB CAFE
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- DBA { Oracle DBA 명령어 > DBA 초급 과정 > DBA 고급 과정 }
- 튜닝 { 오라클 튜닝 목록 }
- 모델링 { 데이터 모델링 가이드 }
목차
1 인덱스 정보[편집]
INDEX 보기
SELECT A.INDEX_NAME
, A.UNIQUENESS
, TO_CHAR(COLUMN_POSITION, '999') AS POS
, SUBSTRB(COLUMN_NAME, 1, 33) AS COLUMN_NAME
FROM USER_INDEXES A
, USER_IND_COLUMNS B
WHERE A.INDEX_NAME = B.INDEX_NAME
AND A.TABLE_OWNER = UPPER('E_LUCIS')
AND A.TABLE_NAME = UPPER('&테이블명')
ORDER BY 1, 3;
1.1 전체 INDEX 보기[편집]
SELECT SUBSTRB(A.TABLE_NAME, 1, 22) AS TABLE_NAME , SUBSTRB(A.INDEX_NAME, 1, 23) AS INDEX_NAME , SUBSTRB(A.UNIQUENESS, 1, 7) AS UNIQUE , TO_CHAR(COLUMN_POSITION, '999') AS POS , SUBSTRB(COLUMN_NAME, 1, 20) AS COLUMN_NAME FROM DBA_INDEXES A , DBA_IND_COLUMNS B WHERE A.INDEX_NAME = B.INDEX_NAME AND A.TABLE_OWNER = B.TABLE_OWNER AND A.TABLE_OWNER = 'E_LUCIS' ORDER BY 1, 2, 3;
1.2 특정 테이블의 인덱스 확인[편집]
인덱스를 확인 하고자 할때 사용하는 쿼리
SELECT C.TABLE_NAME , C.INDEX_NAME , C.COLUMN_NAME , C.COLUMN_POSITION , T.NUM_ROWS
FROM ALL_IND_COLUMNS C
, (SELECT TABLE_NAME, NUM_ROWS
FROM ALL_TABLES
WHERE OWNER = 'ESTDBA'
AND TABLE_NAME IN (SELECT TABLE_NAME
FROM USER_TABLES
WHERE TABLE_NAME LIKE:IN_TABLE_NAME || '%'
)
AND NUM_ROWS > 0
) T
WHERE C.TABLE_NAME = T.TABLE_NAME
ORDER BY T.NUM_ROWS DESC
, C.TABLE_NAME
, C.INDEX_NAME
, C.COLUMN_POSITION;
1.3 인덱스에 대한 컬럼 조회[편집]
SELECT TABLE_NAME , INDEX_NAME , COLUMN_POSITION , COLUMN_NAME
FROM USER_IND_COLUMNS
ORDER BY TABLE_NAME
, INDEX_NAME
, COLUMN_POSITION;
1.4 PRIMARY KEY 재생성 방법[편집]
-- PRIMARY KEY DROP
ALTER TABLE EMP DROP PRIMARY KEY;
-- PRIMARY KEY 생성
ALTER TABLE EMP
ADD CONSTRAINT EMP_PK
PRIMARY KEY(EMPNO) USING INDEX
STORAGE (INITIAL 1M NEXT 1M PCTINCREASE 0)
TABLESPACE USERS;
1.5 PRIMARY KEY를 REFERENCE 하는 FOREIGN KEY 찾기[편집]
SELECT C.NAME CONSTRAINT_NAME FROM DBA_OBJECTS A , CDEF$ B , CON$ C WHERE A.OBJECT_NAME = UPPER('&테이블명') AND A.OBJECT_ID = B.ROBJ# AND B.CON# = C.CON#;
1.5.1 중복인덱스 체크[편집]
SELECT O1.NAME || '.' || N1.NAME REDUNDANT_INDEX, O2.NAME || '.' || N2.NAME SUFFICIENT_INDEX
FROM SYS.ICOL$ IC1 , SYS.ICOL$ IC2 , SYS.IND$ I1 , SYS.OBJ$ N1 , SYS.OBJ$ N2 , SYS.USER$ O1 , SYS.USER$ O2
WHERE IC1.POS# = 1
AND IC2.BO# = IC1.BO#
AND IC2.OBJ#!= IC1.OBJ#
AND IC2.POS# = 1
AND IC2.INTCOL# = IC1.INTCOL#
AND I1.OBJ# = IC1.OBJ#
AND BITAND(I1.PROPERTY, 1) = 0
AND (SELECT MAX(POS#) * (MAX(POS#) + 1) / 2
FROM SYS.ICOL$
WHERE OBJ# = IC1.OBJ#) = (SELECT SUM(XC1.POS#)
FROM SYS.ICOL$ XC1 , SYS.ICOL$ XC2
WHERE XC1.OBJ# = IC1.OBJ#
AND XC2.OBJ# = IC2.OBJ#
AND XC1.POS# = XC2.POS#
AND XC1.INTCOL# = XC2.INTCOL#)
AND N1.OBJ# = IC1.OBJ#
AND N2.OBJ# = IC2.OBJ#
AND O1.USER# = N1.OWNER#
AND O2.USER# = N2.OWNER#;
1.6 테이블의 PK를 구성하는 컬럼 조회[편집]
SELECT A.TABLE_NAME, B.CONSTRAINT_NAME, C.COLUMN_NAME FROM USER_TABLES A , USER_CONSTRAINTS B , USER_CONS_COLUMNS C WHERE A.TABLE_NAME = B.TABLE_NAME AND B.CONSTRAINT_NAME = C.CONSTRAINT_NAME AND B.CONSTRAINT_TYPE = 'P';
1.7 Index가 없는 Table 조회[편집]
SELECT OWNER, TABLE_NAME FROM (SELECT OWNER, TABLE_NAME FROM DBA_TABLES MINUS SELECT TABLE_OWNER, TABLE_NAME FROM DBA_INDEXES) WHERE OWNER NOT IN ('SYS', 'SYSTEM') ORDER BY OWNER, TABLE_NAME;
1.8 인덱스의 Delete Space 조회[편집]
SELECT NAME , LF_ROWS , DEL_LF_ROWS , (DEL_LF_ROWS / LF_ROWS) * 100 AS "DELETE SPACE%"
FROM INDEX_STATS
WHERE NAME = UPPER('&INDEX_NAME');
--Delete Space% 값이 20% 가 넘으면, 그 인덱스는 다시 작성하는 것이 좋다.
1.9 Index가 없는 Table 조회[편집]
SELECT OWNER, TABLE_NAME
FROM (SELECT OWNER, TABLE_NAME
FROM DBA_TABLES
MINUS
SELECT TABLE_OWNER, TABLE_NAME
FROM DBA_INDEXES
)
WHERE OWNER NOT IN ('SYS', 'SYSTEM')
ORDER BY OWNER, TABLE_NAME;
1.10 테이블의 PK를 구성하는 컬럼 조회[편집]
SELECT A.TABLE_NAME, B.CONSTRAINT_NAME, C.COLUMN_NAME
FROM USER_TABLES A
, USER_CONSTRAINTS B
, USER_CONS_COLUMNS C
WHERE A.TABLE_NAME = B.TABLE_NAME
AND B.CONSTRAINT_NAME = C.CONSTRAINT_NAME
AND B.CONSTRAINT_TYPE = 'P';
1.11 인덱스의 Delete Space 조회[편집]
SELECT NAME
, LF_ROWS
, DEL_LF_ROWS
, (DEL_LF_ROWS / LF_ROWS) * 100 AS "DELETE SPACE%"
FROM INDEX_STATS WHERE NAME = UPPER('&INDEX_NAME');
--Delete Space% 값이 20% 가 넘으면, 그 인덱스는 다시 작성하는 것이 좋다.