Oracle 视图 DBA_INDEX_USAGE 官方解释，作用，如何使用详细说明
本站中文解释
视图
Oracle视图 DBA_INDEX_USAGE 用于报告有关Oracle访问索引使用情况的信息，主要用于确定当前存在的索引是否被有效使用。
此视图报告有关相关索引的操作计数，包括索引分析次数、成功的查询次数、失败的查询次数、表的更新次数以及极特殊的无效查询次数。通过分析索引的使用情况，可以找出不必要的索引以及不正确的索引是否被有效使用。
要查看 DBA_INDEX_USAGE 视图，必须具有 SELECT_CATALOG_ROLE 权限，并拥有 DBA 或者 SELECT ANY DICTIONARY 权限。
查看索引使用情况，可以使用以下查询:
SELECT *
FROM DBA_INDEX_USAGE
WHERE owner = ”
AND table_name = ‘
| Column | Datatype | NULL | Description |
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Object ID for the index |
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Index name |
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Index owner |
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Total number of times the index has been accessed |
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Total executions the index has participated in |
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Total rows returned by the index. Index usage is categorized into buckets of different ranges. Each bucket has a range of values for access count and rows returned. An entry is placed into a bucket if the rows returned or access counts falls within the range of that bucket. |
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The index has not been accessed |
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The index has been accessed once |
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The index has been accessed between 2 and 10 times |
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The index has returned between 2 and 10 rows |
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The index has been accessed between 11 and 100 times |
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The index has returned between 11 and 100 rows |
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The index has been accessed between 101 and 1000 times |
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The index has returned between 101 and 1000 rows |
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The index has been accessed more than 1000 times |
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The index has returned more than 1000 rows |
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Time that the index was last used |
See Also:
“V$INDEX_USAGE_INFO”
