SQL Server有哪些隐藏特性?

例如,没有文档的系统存储过程,做一些非常有用但没有足够文档的事情的技巧?


答案

感谢大家的精彩回答!

存储过程

sp_msforeachtable: Runs a command with '?' replaced with each table name (v6.5 and up) sp_msforeachdb: Runs a command with '?' replaced with each database name (v7 and up) sp_who2: just like sp_who, but with a lot more info for troubleshooting blocks (v7 and up) sp_helptext: If you want the code of a stored procedure, view & UDF sp_tables: return a list of all tables and views of database in scope. sp_stored_procedures: return a list of all stored procedures xp_sscanf: Reads data from the string into the argument locations specified by each format argument. xp_fixeddrives:: Find the fixed drive with largest free space sp_help: If you want to know the table structure, indexes and constraints of a table. Also views and UDFs. Shortcut is Alt+F1

片段

Returning rows in random order All database User Objects by Last Modified Date Return Date Only Find records which date falls somewhere inside the current week. Find records which date occurred last week. Returns the date for the beginning of the current week. Returns the date for the beginning of last week. See the text of a procedure that has been deployed to a server Drop all connections to the database Table Checksum Row Checksum Drop all the procedures in a database Re-map the login Ids correctly after restore Call Stored Procedures from an INSERT statement Find Procedures By Keyword Drop all the procedures in a database Query the transaction log for a database programmatically.

功能

哈希字节() EncryptByKey 枢轴命令

Misc

Connection String extras TableDiff.exe Triggers for Logon Events (New in Service Pack 2) Boosting performance with persisted-computed-columns (pcc). DEFAULT_SCHEMA setting in sys.database_principles Forced Parameterization Vardecimal Storage Format Figuring out the most popular queries in seconds Scalable Shared Databases Table/Stored Procedure Filter feature in SQL Management Studio Trace flags Number after a GO repeats the batch Security using schemas Encryption using built in encryption functions, views and base tables with triggers


当前回答

跟踪旗帜!“1204”在SQL Server 2000上的死锁调试中是无价的(2005有更好的工具)。

其他回答

Vardecimal存储格式

SQL Server 2005为数字和十进制数据类型添加了一种新的存储格式,称为vardecimal。Vardecimal是十进制类型的一种变长表示,可以在行的每个实例中保存未使用的字节。如果十进制定义很大(如decimal(38,6)),但存储的值很小(如0.0),或者有大量重复值,或者数据填充稀疏,则可以节省最多的时间。

Link

用于解析存储过程参数:xp_sscanf

将数据从字符串读入每个格式参数指定的参数位置。 下面的示例使用xp_sscanf 从源中提取两个值 属性中的位置 源字符串的格式。

DECLARE @filename varchar (20), @message varchar (20)
EXEC xp_sscanf 'sync -b -fproducts10.tmp -rrandom', 'sync -b -f%s -r%s', 
  @filename OUTPUT, @message OUTPUT
SELECT @filename, @message

这是结果集。

-------------------- -------------------- 
products10.tmp        random

表/存储过程过滤器是一个半隐藏的特性,非常有用…

在“SQL Server Management Studio对象资源管理器”中,右键单击“表或存储过程”文件夹,选择“筛选器”菜单,然后选择“筛选器设置”,并在“名称包含”行中输入部分名称。

同样地,使用Remove Filter再次查看所有表/存储过程。

我不确定这是否是一个隐藏的功能,但我偶然发现了这个功能,并发现它在很多情况下都很有用。您可以在单个选择语句中连接一组字段,而不是使用游标并遍历选择语句。

例子:

DECLARE @nvcConcatonated nvarchar(max)
SET @nvcConcatonated = ''

SELECT @nvcConcatonated = @nvcConcatonated + C.CompanyName + ', '
FROM tblCompany C
WHERE C.CompanyID IN (1,2,3)

SELECT @nvcConcatonated

结果:

Acme, Microsoft, Apple,

可伸缩的共享数据库

通过可伸缩共享数据库,可以在普通机器上挂载相同的物理驱动器,并允许多个SQL Server 2005实例使用同一组数据文件。这种设置不需要为每个SQL Server实例复制存储,并且允许多个SQL Server实例具有额外的处理能力,这些实例具有自己的本地资源,如cpu、内存、tempdb和其他潜在的本地数据库。

Link