使用SQL Server数据库的时候，数据库耗资源很大、卡死，怎么办？可以试着找找是否有执行很慢的SQL语句......
选择【master】数据库，点击【新建查询】，执行SQL语句：
SELECT TOP 30
total_worker_time/1000 AS [CPU总耗时(ms)],
execution_count [运行次数],
qs.total_worker_time/qs.execution_count/1000 AS [CPU平均耗时(ms)],
last_execution_time AS [最后执行时间],
max_worker_time/1000 AS [最大执行耗时(ms)],
SUBSTRING(,qs.statement_start_offset/2+1,
(CASE WHEN qs.statement_end_offset = -1
THEN DATALENGTH()
ELSE qs.statement_end_offset
END -qs.statement_start_offset)/2 + 1) AS [SQL语句]
FROM sys.dm_exec_query_stats qs WITH(nolock)
CROSS apply sys.dm_exec_sql_text(qs.sql_handle) AS qt
WHERE execution_count > 1
ORDER BY max_worker_time DESC