sqlserver数据库连接数相关问题

sql语句监控连接数量

SELECT  ec.client_net_address ,
        es.[program_name] ,
        es.[host_name] ,
        es.login_name ,
        COUNT(ec.session_id) AS [connection count]
FROM    sys.dm_exec_sessions AS es
        INNER JOIN sys.dm_exec_connections AS ec ON es.session_id = ec.session_id
GROUP BY ec.client_net_address ,
        es.[program_name] ,
        es.[host_name] ,
        es.login_name
ORDER BY [connection count] desc

设置最大连接池数量

在连接字符串中加上 "max pool size=512;  ",如果不设置的话,默认为100

避免数据库连接数过高

1.合理使用缓存,减少数据库请求量

2.检查慢sql并优化

SELECT TOP 20
    total_worker_time/1000 AS [总消耗CPU 时间(ms)],execution_count [运行次数],
    qs.total_worker_time/qs.execution_count/1000 AS [平均消耗CPU 时间(ms)],
    last_execution_time AS [最后一次执行时间],max_worker_time /1000 AS [最大执行时间(ms)],
    SUBSTRING(qt.text,qs.statement_start_offset/2+1,
        (CASE WHEN qs.statement_end_offset = -1
        THEN DATALENGTH(qt.text)
        ELSE qs.statement_end_offset END -qs.statement_start_offset)/2 + 1)
    AS [使用CPU的语法], qt.text [完整语法],
    dbname=db_name(qt.dbid),
    object_name(qt.objectid,qt.dbid) ObjectName
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 /1000 DESC