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

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。

其他回答

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,

下面是一些我喜欢的SQL Management Studio隐藏特性。

我喜欢的一点是,如果你在高亮显示信息时按住ALT键,你可以选择柱状信息,而不仅仅是整行。

在SQL Management Studio中,你有预定义的快捷键:

Ctrl+1运行sp_who Ctrl+2运行sp_lock Alt+F1运行sp_help Ctrl+F1运行sp_helptext

因此,如果您在编辑器中突出显示表名并按Alt+F1,它将显示表的结构。

SQL Server 2005:

select * from sys.dm_os_performance_counters

select * from sys.dm_exec_requests
sp_executesql 

用于执行字符串中的语句。与Execute一样好,但可以返回参数

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