在Oracle中,如何知道哪些外键未创建索引?
可以通过如下的SQL语句来查询到哪些外键未创建索引:
SELECT OWNER,
TABLE_NAME,
CONSTRAINT_NAME,
CNAME1 || NVL2(CNAME2, ',' || CNAME2, NULL) ||
NVL2(CNAME3, ',' || CNAME3, NULL) ||
NVL2(CNAME4, ',' || CNAME4, NULL) ||
NVL2(CNAME5, ',' || CNAME5, NULL) ||
NVL2(CNAME6, ',' || CNAME6, NULL) ||
NVL2(CNAME7, ',' || CNAME7, NULL) ||
NVL2(CNAME8, ',' || CNAME8, NULL) COLUMNS
FROM (SELECT B.OWNER,
B.TABLE_NAME,
B.CONSTRAINT_NAME,
MAX(DECODE(POSITION, 1, COLUMN_NAME, NULL)) CNAME1,
MAX(DECODE(POSITION, 2, COLUMN_NAME, NULL)) CNAME2,
MAX(DECODE(POSITION, 3, COLUMN_NAME, NULL)) CNAME3,
MAX(DECODE(POSITION, 4, COLUMN_NAME, NULL)) CNAME4,
MAX(DECODE(POSITION, 5, COLUMN_NAME, NULL)) CNAME5,
MAX(DECODE(POSITION, 6, COLUMN_NAME, NULL)) CNAME6,
MAX(DECODE(POSITION, 7, COLUMN_NAME, NULL)) CNAME7,
MAX(DECODE(POSITION, 8, COLUMN_NAME, NULL)) CNAME8,
COUNT(*) COL_CNT
FROM (SELECT SUBSTR(TABLE_NAME, 1, 30) TABLE_NAME,
SUBSTR(CONSTRAINT_NAME, 1, 30) CONSTRAINT_NAME,
SUBSTR(COLUMN_NAME, 1, 30) COLUMN_NAME,
POSITION
FROM DBA_CONS_COLUMNS
WHERE OWNER NOT IN
('XDB', 'APEX_030200', 'DBSNMP', 'ORDDATA','DB_MONITOR','LHR','SH')
AND OWNER NOT LIKE '%SYS%') A,
DBA_CONSTRAINTS B
WHERE A.CONSTRAINT_NAME = B.CONSTRAINT_NAME
AND B.CONSTRAINT_TYPE = 'R'
AND B.OWNER NOT IN ('XDB', 'APEX_030200', 'DBSNMP', 'ORDDATA','DB_MONITOR','LHR','SH')
AND B.OWNER NOT LIKE '%SYS%'
GROUP BY B.OWNER, B.TABLE_NAME, B.CONSTRAINT_NAME) CONS
WHERE COL_CNT > ALL (SELECT COUNT(*)
FROM DBA_IND_COLUMNS I
WHERE I.TABLE_NAME = CONS.TABLE_NAME
AND I.COLUMN_NAME IN (CNAME1,
CNAME2,
CNAME3,
CNAME4,
CNAME5,
CNAME6,
CNAME7,
CNAME8)
AND I.COLUMN_POSITION <= CONS.COL_CNT
AND I.INDEX_OWNER NOT IN
('XDB', 'APEX_030200', 'DBSNMP', 'ORDDATA','DB_MONITOR','LHR','SH')
AND INDEX_OWNER NOT LIKE '%SYS%'
GROUP BY I.INDEX_NAME);
● 本文作者:小麦苗,只专注于数据库的技术,更注重技术的运用
● 作者博客地址:http://blog.itpub.net/26736162/abstract/1/
● 本系列题目来源于作者的学习笔记,部分整理自网络,若有侵权或不当之处还请谅解
● 版权所有,欢迎分享本文,转载请保留出处
● QQ:646634621 QQ群:230161599
● 题目解答若有不当之处,还望各位朋友批评指正,共同进步
长按下图识别二维码或微信扫描下图二维码来关注小麦苗的微信公众号:xiaomaimiaolhr,学习最实用的数据库技术。




