--当前的数据库用户连接情况--

1 SELECT * FROM sys.[sysprocesses] WHERE [spid]>50 AND DB_NAME([dbid])='db_name'
2 SELECT * FROM [sys].[dm_exec_sessions] WHERE [session_id]>50

 

---选取了前10个最耗CPU时间的会话--

 1 SELECT TOP 10
 2 [session_id],
 3 [request_id],
 4 [start_time] AS '开始时间',
 5 [status] AS '状态',
 6 [command] AS '命令',
 7 dest.[text] AS 'sql语句', 
 8 DB_NAME([database_id]) AS '数据库名',
 9 [blocking_session_id] AS '正在阻塞其他会话的会话ID',
10 [wait_type] AS '等待资源类型',
11 [wait_time] AS '等待时间',
12 [wait_resource] AS '等待的资源',
13 [reads] AS '物理读次数',
14 [writes] AS '写次数',
15 [logical_reads] AS '逻辑读次数',
16 [row_count] AS '返回结果行数'
17 FROM sys.[dm_exec_requests] AS der 
18 CROSS APPLY 
19 sys.[dm_exec_sql_text](der.[sql_handle]) AS dest 
20 WHERE [session_id]>50 AND DB_NAME(der.[database_id])='db_name' 
21 ORDER BY [cpu_time] DESC

---选取了前10个最耗CPU时间的SQL---

1 SELECT TOP 10 
2 dest.[text] AS 'sql语句'
3 FROM sys.[dm_exec_requests] AS der 
4 CROSS APPLY 
5 sys.[dm_exec_sql_text](der.[sql_handle]) AS dest 
6 WHERE [session_id]>50 
7 ORDER BY [cpu_time] DESC

 

 1 SELECT TOP 10
 2 total_worker_time/execution_count AS avg_cpu_cost, plan_handle,
 3 execution_count,
 4 (SELECT SUBSTRING(text, statement_start_offset/2 + 1,
 5 (CASE WHEN statement_end_offset = -1
 6 THEN LEN(CONVERT(nvarchar(max), text)) * 2
 7 ELSE statement_end_offset
 8 END - statement_start_offset)/2)
 9 FROM sys.dm_exec_sql_text(sql_handle)) AS query_text
10 FROM sys.dm_exec_query_stats
11 ORDER BY [avg_cpu_cost] DESC

----查询缺失索引----

1 SELECT 
2 DatabaseName = DB_NAME(database_id)
3 ,[Number Indexes Missing] = count(*) 
4 FROM sys.dm_db_missing_index_details
5 GROUP BY DB_NAME(database_id)
6 ORDER BY 2 DESC;

 

 1 SELECT TOP 10 
 2 [Total Cost] = ROUND(avg_total_user_cost * avg_user_impact * (user_seeks + user_scans),0) 
 3 , avg_user_impact
 4 , TableName = statement
 5 , [EqualityUsage] = equality_columns 
 6 , [InequalityUsage] = inequality_columns
 7 , [Include Cloumns] = included_columns
 8 FROM sys.dm_db_missing_index_groups g 
 9 INNER JOIN sys.dm_db_missing_index_group_stats s 
10 ON s.group_handle = g.index_group_handle 
11 INNER JOIN sys.dm_db_missing_index_details d 
12 ON d.index_handle = g.index_handle
13 ORDER BY [Total Cost] DESC;