Oracle 视图 DBA_ADVISOR_SQLSTATS 官方解释，作用，如何使用详细说明
本站中文解释
Oracle视图DBA_ADVISOR_SQLSTATS显示SQL优化器性能统计信息，可用于发现SQL优化器中的性能问题，并做出改进措施。它使用静态变量来保存特定的优化者行为，其中包括给定的SQL的次数，执行次数，优化次数，最小执行时间，最大执行时间，平均执行时间，平均优化时间，缓冲区命中次数，直接I/O次数，CPU使用等等。要使用这个视图，可以使用如下语句：
SELECT * FROM dba_advisor_sqlstats;
这将返回用于该步骤的SQL的统计数据的完整列表。另外，也可以使用WHERE子句来缩小结果集，使用AND条件来定位来自特定操作的SQL。
官方英文解释
DBA_ADVISOR_SQLSTATS displays execution statistics for the test-execution of different SQL plans during the advisor analysis.
Related View
USER_ADVISOR_SQLSTATS displays execution statistics owned by the current user for the test-execution of different SQL plans during the advisor analysis.
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Advisor task name in which the SQL statement was executed (see |
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Advisor task ID in which the SQL statement was executed (see |
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Advisor task execution in which the SQL statement was executed (see |
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Type of the advisor task execution in which the SQL statement was executed (see |
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Advisor object ID identifying the relevant SQL statement (see |
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Plan ID number generated to uniquely identify a plan for a particular SQL statement (foreign key to |
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Identifier for the SQL statement executed |
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Hash value of the SQL execution plan |
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For internal use only |
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The database ID of the pluggable database (PDB) |
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Parse time (in microseconds) measured for the SQL |
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Elapsed time (in microseconds) to execute the SQL and fetch all of its rows, after parsing |
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CPU time (in microseconds) to execute the SQL and fetch all of its rows, after parsing |
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I/O time (in microseconds) to execute the SQL and fetch all of its rows, after parsing |
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Number of buffer gets measured for executing the SQL and fetching all of its rows |
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Number of disk reads measured for executing the SQL and fetching all of its rows |
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Number of direct writes measured for executing the SQL and fetching all of its rows |
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Number of physical read I/O requests issued by the monitored SQL |
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Number of physical write I/O requests issued by the monitored SQL |
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Number of bytes read from disks by the monitored SQL |
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Number of bytes written to disks by the monitored SQL |
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Number of rows returned by the SQL execution |
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Number of fetches for the SQL execution |
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Execution count for the SQL. This column will always have a value of |
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Indicates whether the SQL was executed to end-of-fetch ( |
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Optimizer cost for the execution plan |
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For internal use only |
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Total number of executions during test execute |
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Number of I/O bytes exchanged between Oracle Database and the storage system |
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Indicates whether the first execution in test execute is ignored ( |
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The database ID of the PDB |
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For internal use only |
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For internal use only |
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The total of the db block gets from cache statistic and the consistent gets from cache statistic |
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The total of the db block gets direct statistic and the consistent gets direct statistic |
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Number of original executions from the SQL tuning set, independent of trial executions |
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Value of the flags from the execution of the SQL, such as timeout or error |
See Also:
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“USER_ADVISOR_SQLSTATS”
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“Statistics Descriptions” for more information about statistics
