Sql Server数据库实用命令

1.清理日志语句:当日志容量过大时

backup log isale with NO_LOG;
backup log isale with TRUNCATE_ONLY;
DBCC SHRINKDATABASE(isale);

2.Sql Server自动备份语句

declare @filename nvarchar(100) set @filename='D:dbstore/isale'+replace(replace(replace(CONVERT(varchar, getdate(), 120 ),'-',''),' ',''),':','')
+'.bak'

BACKUP DATABASE [isale] TO DISK =@filename
WITH NOFORMAT, INIT,
NAME = N'isale-完整 数据库 备份', SKIP, NOREWIND, NOUNLOAD, STATS = 10

3.Sql Server查看索引碎片

use databaseName

DBCC SHOWCONTIG

eg:对于单表

use isale
DBCC SHOWCONTIG (branch_move_in)

DBCC SHOWCONTIG scanning 'Employee' table... 

Table: 'Employee' (1195151303); index ID: 1, database ID: 53 

TABLE level scan performed. 

- Pages Scanned................................: 179 

- Extents Scanned..............................: 24 

- Extent Switches..............................: 24 

- Avg. Pages per Extent........................: 7.5 

- Scan Density [Best Count:Actual Count].......: 92.00% [23:25] 

- Logical Scan Fragmentation ..................: 0.56% 

- Extent Scan Fragmentation ...................: 12.50% 

- Avg. Bytes Free per Page.....................: 552.3 

- Avg. Page Density (full).....................: 93.18% 

DBCC execution completed.


信息  描述

Pages Scanned   表或索引中的长页数

Extents Scanned 表或索引中的长区页数

Extent Switches  DBCC遍历页时从一个区域到另一个区域的次数

Avg. Pages per Extent      相关区域中的页数

Scan Density[Best Count:Actual Count]

Best Count是连续链接时的理想区域改变数，Actual Count是实际区域改变，

Scan Density为100%表示没有分块。

Logical Scan Fragmentation   扫描索引页中失序页的百分比

Extent Scan Fragmentation    不实际相邻和包含链路中所有链接页的区域数

Avg. Bytes Free per Page       扫描页面中平均自由字节数

Avg. Page Density (full) 平均页密度，表示页有多满

重修复索引：
DBCC DBREINDEX (branch_move_in)

4.Sql Server检查数据库状态

DBCC CHECKDB