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

/*找到空闲空间最大的固定驱动器,也可以复制文件来估计哪个磁盘最快*/

EXEC master..xp_fixeddrives

/*在使用或引用之前检查文件的假设*/

EXEC master..xp_fileexist 'C:\file_you_want_to_check'

详情请点击这里

其他回答

替代Kolten的sp_change_users_login:

ALTER USER wacom_app WITH LOGIN = wacom_app

HashBytes()返回其输入的MD2、MD4、MD5、SHA或SHA1哈希值。

在SQL Server 2005/2008中显示SELECT查询结果中的行号:

SELECT ( ROW_NUMBER() OVER (ORDER BY OrderId) ) AS RowNumber,
        GrandTotal, CustomerId, PurchaseDate
FROM Orders

ORDER BY是一个强制性条款。OVER()子句告诉SQL引擎对指定列(在本例中为OrderId)上的数据进行排序,并根据排序结果分配数字。

批分离器

大多数人都不知道“GO”不是SQL命令。它是客户端工具使用的默认批处理分隔符。你可以在Books Online找到更多信息。

您可以通过在Management Studio中选择“Tools -> Options”,并在“查询执行”部分更改批量分隔符选项来更改批量分隔符选项。

我不知道为什么你想这样做,除了作为一个恶作剧,但这是一个有点有趣的琐事。

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