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更新时间:2022-12-07 GMT+08:00

RDS SQL Server支持DMV动态管理视图

RDS for SQL Server支持DMV动态管理视图,方便用户快速查询实例上性能消耗最高的10条SQL语句。

操作场景

  • 数据库执行效率较低。
  • 某些时段的CPU,IO较高。

操作步骤

  1. 登录SQL SERVER客户端,通过rdsuser帐号连接目标实例,在管理面中执行以下SQL语句。

    declare @DatabaseName nvarchar(100)
    set @DatabaseName = 'Wisdom_TT_ODS'
    
    select top 100
    DB_NAME(st.dbid) as DBName, OBJECT_NAME(st.objectid,st.dbid) as ObjectName,
    substring(st.text,(qs.statement_start_offset/2)+1,((case qs.statement_end_offset when -1 then datalength(st.text) else qs.statement_end_offset end - qs.statement_start_offset)/2) + 1) as Statement,
    st.text as Query,
    qp.query_plan,
    plan_generation_num,
    creation_time,
    last_execution_time,
    execution_count,
    total_worker_time,
    min_worker_time,
    max_worker_time,
    total_logical_reads,
    min_logical_reads,
    max_logical_reads,
    total_elapsed_time,
    min_elapsed_time,
    max_elapsed_time,
    total_rows,
    min_rows,
    max_rows,
    total_worker_time/execution_count as avg_worker_time,                            --平均CPU耗时
    total_logical_reads/execution_count as avg_logical_reads,                        --平均逻辑读
    total_elapsed_time/execution_count as avg_elapsed_time,                          --平均总耗时
    total_rows/execution_count as avg_rows,                                          --平均处理数据行
    sql_handle,
    plan_handle,
    query_hash,
    query_plan_hash
    from sys.dm_exec_query_stats qs
    cross apply sys.dm_exec_sql_text(plan_handle) st
    cross apply sys.dm_exec_query_plan(plan_handle) qp
    where st.dbid=DB_ID(@DatabaseName)
    and text not like '%sys.%'and text not like '%[[]sys]%'
    order by avg_worker_time desc

  2. 查看结果中对应数据库的SQL执行记录及资源消耗情况。