sqlserver性能调优常用方法

1.检查数据库空间使用情况，查看哪些表占用了比较大的磁盘空间

执行语句如下：

select o.name,
        SUM(p.reserved_page_count) as reserved_page_count,
        SUM(p.used_page_count) as used_page_count,
        SUM(
        case
        when(p.index_id<2) then (p.in_row_data_page_count+
        p.lob_used_page_count+p.row_overflow_used_page_count)
        else p.lob_used_page_count+p.row_overflow_used_page_count
        end
        ) as DataPages,
        SUM(
        case
        when (p.index_id<2) then row_count
        else 0
        end
        ) as rowCounts
        from sys.dm_db_partition_stats p inner join sys.objects o
        on p.object_id=o.object_id
        group by o.name
        order by rowCounts desc

2.通过活动监视器查看性能消耗

通过磁盘IO，CPU占用时间，逻辑读写的次数来判断哪些语句消耗性能比较大

3.通过执行时间，磁盘IO和执行计划查看sql语句情况，包括编译执行时间，索引扫描查找，读写等等

查看sql语句的执行时间和表扫描，逻辑读写情况的语句：

SET STATISTICS TIME ON
SET STATISTICS IO ON