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丸趣 TV 小編給大家分享一下 Oracle 中如何找出有哪些索引從來沒有被使用過,相信大部分人都還不怎么了解,因此分享這篇文章給大家參考一下,希望大家閱讀完這篇文章后大有收獲,下面讓我們一起去了解一下吧!
數(shù)據(jù)庫(kù)經(jīng)過 N 手后,索引亂建,下面的 SQL 就找出一點(diǎn)時(shí)間范圍內(nèi)哪些索引從來沒被使用過,親測(cè)好用,注意一點(diǎn),生成的 SQL 你要是執(zhí)行了,就會(huì)從腳本中消失了,
SELECT X.OWNER,
X.TABLE_NAME,
X.INDEX_NAME,
C.COLUMN_POSITION,
C.COLUMN_NAME,
S.BYTES / 1024 / 1024 M,
q [select count(*),count(distinct ] || C.COLUMN_NAME ||
q [) from ] || X.OWNER || . || X.TABLE_NAME || q ] AS QUERY_Q
FROM (SELECT A.OWNER, A.TABLE_NAME, A.INDEX_NAME
FROM DBA_INDEXES A
WHERE A.OWNER IN (SELECT USERNAME
FROM DBA_USERS
WHERE CREATED DATE 2018-10-30 )
AND (A.OWNER, A.INDEX_NAME) NOT IN
(SELECT /*+unnest*/
B.OBJECT_OWNER, B.OBJECT_NAME
FROM GV$SQL A, GV$SQL_PLAN B
WHERE A.SQL_ID = B.SQL_ID
AND A.CHILD_NUMBER = B.CHILD_NUMBER
AND B.OBJECT_OWNER IN
(SELECT USERNAME
FROM DBA_USERS
WHERE CREATED DATE 2018-10-30 )
AND B.OBJECT_TYPE LIKE %INDEX%
AND B.TIMESTAMP DATE 2018-10-10 )
AND A.TABLE_NAME NOT LIKE SYS%
AND A.UNIQUENESS UNIQUE ) X
INNER JOIN DBA_IND_COLUMNS C
ON C.INDEX_OWNER = X.OWNER
AND C.INDEX_NAME = X.INDEX_NAME
AND C.TABLE_NAME = X.TABLE_NAME
INNER JOIN DBA_SEGMENTS S
ON S.SEGMENT_NAME = C.TABLE_NAME
AND S.OWNER = C.INDEX_OWNER
AND S.BYTES / 1024 / 1024 10
ORDER BY 1, 2, 3, 4;
以上是“Oracle 中如何找出有哪些索引從來沒有被使用過”這篇文章的所有內(nèi)容,感謝各位的閱讀!相信大家都有了一定的了解,希望分享的內(nèi)容對(duì)大家有所幫助,如果還想學(xué)習(xí)更多知識(shí),歡迎關(guān)注丸趣 TV 行業(yè)資訊頻道!
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