SQL优化方法：

1 USE master
2 GO
3 --如果要指定数据库就把注释去掉
4 SELECT * FROM sys.[sysprocesses] WHERE [spid]>50 --AND DB_NAME([dbid])&＃61;&＃39;gposdb&＃39;

1 SELECT TOP 102 [session_id],3 [request_id],4 [start_time] AS &＃39;开始时间&＃39;,5 [status] AS &＃39;状态&＃39;,6 [command] AS &＃39;命令&＃39;,7 dest.[text] AS &＃39;sql语句&＃39;, 8 DB_NAME([database_id]) AS &＃39;数据库名&＃39;,9 [blocking_session_id] AS &＃39;正在阻塞其他会话的会话ID&＃39;,
10 [wait_type] AS &＃39;等待资源类型&＃39;,
11 [wait_time] AS &＃39;等待时间&＃39;,
12 [wait_resource] AS &＃39;等待的资源&＃39;,
13 [reads] AS &＃39;物理读次数&＃39;,
14 [writes] AS &＃39;写次数&＃39;,
15 [logical_reads] AS &＃39;逻辑读次数&＃39;,
16 [row_count] AS &＃39;返回结果行数&＃39;
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])&＃61;&＃39;gposdb&＃39;
21 ORDER BY [cpu_time] DESC

1 --在SSMS里选择以文本格式显示结果
2 SELECT TOP 10
3 dest.[text] AS &＃39;sql语句&＃39;
4 FROM sys.[dm_exec_requests] AS der
5 CROSS APPLY
6 sys.[dm_exec_sql_text](der.[sql_handle]) AS dest
7 WHERE [session_id]>50
8 ORDER BY [cpu_time] DESC

1 SELECT TOP 102 [session_id],3 [request_id],4 [start_time] AS &＃39;开始时间&＃39;,5 [status] AS &＃39;状态&＃39;,6 [command] AS &＃39;命令&＃39;,7 dest.[text] AS &＃39;sql语句&＃39;, 8 DB_NAME([database_id]) AS &＃39;数据库名&＃39;,9 [blocking_session_id] AS &＃39;正在阻塞其他会话的会话ID&＃39;,
10 der.[wait_type] AS &＃39;等待资源类型&＃39;,
11 [wait_time] AS &＃39;等待时间&＃39;,
12 [wait_resource] AS &＃39;等待的资源&＃39;,
13 [dows].[waiting_tasks_count] AS &＃39;当前正在进行等待的任务数&＃39;,
14 [reads] AS &＃39;物理读次数&＃39;,
15 [writes] AS &＃39;写次数&＃39;,
16 [logical_reads] AS &＃39;逻辑读次数&＃39;,
17 [row_count] AS &＃39;返回结果行数&＃39;
18 FROM sys.[dm_exec_requests] AS der
19 INNER JOIN [sys].[dm_os_wait_stats] AS dows
20 ON der.[wait_type]&＃61;[dows].[wait_type]
21 CROSS APPLY
22 sys.[dm_exec_sql_text](der.[sql_handle]) AS dest
23 WHERE [session_id]>50
24 ORDER BY [cpu_time] DESC

1 SELECT TOP 102 total_worker_time/execution_count AS avg_cpu_cost, plan_handle,3 execution_count,4 (SELECT SUBSTRING(text, statement_start_offset/2 &＃43; 1,5 (CASE WHEN statement_end_offset &＃61; -16 THEN LEN(CONVERT(nvarchar(max), text)) * 27 ELSE statement_end_offset8 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

1 SELECT 2 DatabaseName &＃61; DB_NAME(database_id)3 ,[Number Indexes Missing] &＃61; count(*) 4 FROM sys.dm_db_missing_index_details5 GROUP BY DB_NAME(database_id)6 ORDER BY 2 DESC;7 SELECT TOP 10 8 [Total Cost] &＃61; ROUND(avg_total_user_cost * avg_user_impact * (user_seeks &＃43; user_scans),0) 9 , avg_user_impact
10 , TableName &＃61; statement
11 , [EqualityUsage] &＃61; equality_columns
12 , [InequalityUsage] &＃61; inequality_columns
13 , [Include Cloumns] &＃61; included_columns
14 FROM sys.dm_db_missing_index_groups g
15 INNER JOIN sys.dm_db_missing_index_group_stats s
16 ON s.group_handle &＃61; g.index_group_handle
17 INNER JOIN sys.dm_db_missing_index_details d
18 ON d.index_handle &＃61; g.index_handle
19 ORDER BY [Total Cost] DESC;