-- 查询执行中sql语句
SELECT TOP 500
[session_id],
[request_id],
[start_time] AS '开始时间',
getdate() as 当前时间,
[status] AS '状态',
[command] AS '命令',
dest.[text] AS 'sql语句',
DB_NAME([database_id]) AS '数据库名',
[blocking_session_id] AS '正在阻塞其他会话的会话ID',
[wait_type] AS '等待资源类型',
[wait_time] AS '等待时间',
[wait_resource] AS '等待的资源',
[reads] AS '物理读次数',
[writes] AS '写次数',
[logical_reads] AS '逻辑读次数',
[row_count] AS '返回结果行数'
FROM sys.[dm_exec_requests] AS der
CROSS APPLY
sys.[dm_exec_sql_text](der.[sql_handle]) AS dest
ORDER BY 开始时间
-- 查询SqlServer总体的内存使用情况
select type , sum(virtual_memory_reserved_kb) VM_Reserved , sum(virtual_memory_committed_kb) VM_Commited , sum(awe_allocated_kb) AWE_Allocated , sum(shared_memory_reserved_kb) Shared_Reserved , sum(shared_memory_committed_kb) Shared_Commited --, sum(single_pages_kb) --SQL2005、2008 --, sum(multi_pages_kb) --SQL2005、2008 from sys.dm_os_memory_clerks group by type order by type
-- 查询当前数据库缓存的所有数据页面，哪些数据表，缓存的数据页面数量 -- 从这些信息可以看出，系统经常要访问的都是哪些表，有多大？
select p.object_id, object_name=object_name(p.object_id), p.index_id, buffer_pages=count(*) from sys.allocation_units a, sys.dm_os_buffer_descriptors b, sys.partitions p where a.allocation_unit_id=b.allocation_unit_id and a.container_id=p.hobt_id and b.database_id=db_id() group by p.object_id,p.index_id order by buffer_pages desc
-- 查询缓存的各类执行计划，及分别占了多少内存
-- 可以对比动态查询与参数化SQL（预定义语句）的缓存量
select cacheobjtype , objtype , sum(cast(size_in_bytes as bigint))/1024 as size_in_kb , count(bucketid) as cache_count from sys.dm_exec_cached_plans group by cacheobjtype, objtype order by cacheobjtype, objtype
-- 查询缓存中具体的执行计划，及对应的SQL
-- 将此结果按照数据表或SQL进行统计，可以作为基线，调整索引时考虑
-- 查询结果会很大，注意将结果集输出到表或文件中
SELECT usecounts , refcounts , size_in_bytes , cacheobjtype , objtype , TEXT FROM sys.dm_exec_cached_plans cp CROSS APPLY sys.dm_exec_sql_text(plan_handle) ORDER BY objtype DESC ;?