查询执行中最慢的SQL语句 / 查询表占用空间 / 查询表字段结构设计

--查询表字段结构设计

SELECT
     表名       = case when a.colorder=1 then d.name else '' end,
     表说明     = case when a.colorder=1 then isnull(f.value,'') else '' end,
     字段序号   = a.colorder,
     字段名     = a.name,
     标识       = case when COLUMNPROPERTY( a.id,a.name,'IsIdentity')=1 then '√'else '' end,
     主键       = case when exists(SELECT 1 FROM sysobjects where xtype='PK' and parent_obj=a.id and name in (
                      SELECT name FROM sysindexes WHERE indid in( SELECT indid FROM sysindexkeys WHERE id = a.id AND colid=a.colid))) then '√' else '' end,
     类型       = b.name,
     占用字节数 = a.length,
     长度       = COLUMNPROPERTY(a.id,a.name,'PRECISION'),
     小数位数   = isnull(COLUMNPROPERTY(a.id,a.name,'Scale'),0),
     允许空     = case when a.isnullable=1 then '√'else '' end,
     默认值     = isnull(e.text,''),
     字段说明   = isnull(g.[value],'')
 FROM  syscolumns a
 left join  systypes b  on  a.xusertype=b.xusertype inner join  sysobjects d  on  a.id=d.id  and d.xtype='U' and  d.name<>'dtproperties'
 left join  syscomments e  on  a.cdefault=e.id left join sys.extended_properties   g  on  a.id=G.major_id and a.colid=g.minor_id  
 left join  sys.extended_properties f on d.id=f.major_id and f.minor_id=0
 --where
     --d.name='Sys_User'    --如果只查询指定表,加上此where条件，tablename是要查询的表名；去除where条件查询所有的表信息
 order by  a.id,a.colorder

 

--查询表占用空间
SELECT
    t.NAME AS TableName,
    p.rows AS RowCounts,
    SUM(a.total_pages) * 8 AS TotalSpaceKB,
    SUM(a.used_pages) * 8 AS UsedSpaceKB,
    (SUM(a.total_pages) - SUM(a.used_pages)) * 8 AS UnusedSpaceKB
FROM
    sys.tables t
INNER JOIN     
    sys.indexes i ON t.OBJECT_ID = i.object_id
INNER JOIN
    sys.partitions p ON i.object_id = p.OBJECT_ID AND i.index_id = p.index_id
INNER JOIN
    sys.allocation_units a ON p.partition_id = a.container_id
WHERE
    t.NAME NOT LIKE 'dt%'
    AND t.is_ms_shipped = 0
    AND i.OBJECT_ID > 255
GROUP BY
    t.NAME, p.Rows
ORDER BY
    TotalSpaceKB DESC; --总空间KB
    --RowCounts DESC; --行数
    --UsedSpaceKB desc -- 已使用空间KB
    --UnusedSpaceKB desc --未使用空间KB

 

 

 

--查看当前占用 cpu 资源最高的会话和其中执行的语句(及时CPU)
select spid,cmd,cpu,physical_io,memusage,
(select top 1 [text] from ::fn_get_sql(sql_handle)) sql_text
from master..sysprocesses order by cpu desc,physical_io desc

--总耗CPU最多的前个SQL:
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],qt.dbid, dbname=db_name(qt.dbid),qt.objectid,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  total_worker_time DESC

--执行最慢的SQL语句
SELECT
(total_elapsed_time / execution_count)/1000 N'平均时间ms'
,total_elapsed_time/1000 N'总花费时间ms'
,total_worker_time/1000 N'所用的CPU总时间ms'
,total_physical_reads N'物理读取总次数'
,total_logical_reads/execution_count N'每次逻辑读次数'
,total_logical_reads N'逻辑读取总次数'
,total_logical_writes N'逻辑写入总次数'
,execution_count N'执行次数'
,SUBSTRING(st.text, (qs.statement_start_offset/2) + 1,
((CASE statement_end_offset
WHEN -1 THEN DATALENGTH(st.text)
ELSE qs.statement_end_offset END
- qs.statement_start_offset)/2) + 1) N'执行语句'
,creation_time N'语句编译时间'
,last_execution_time N'上次执行时间'
FROM
sys.dm_exec_query_stats AS qs CROSS APPLY sys.dm_exec_sql_text(qs.sql_handle) st
WHERE
SUBSTRING(st.text, (qs.statement_start_offset/2) + 1,
((CASE statement_end_offset
WHEN -1 THEN DATALENGTH(st.text)
ELSE qs.statement_end_offset END
- qs.statement_start_offset)/2) + 1) not like 'tch%'
ORDER BY
total_elapsed_time / execution_count DESC;