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

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

其他回答

有时没有合适的列来排序,或者您只是想要表上的默认排序顺序,并且希望枚举每一行。为了做到这一点,你可以把“(select 1)”放在“order by”子句中,你就会得到你想要的东西。整洁的,是吗?

select row_number() over (order by (select 1)), * from dbo.Table as t

本周我学到的最令人惊讶的事情是在ORDER By子句中使用CASE语句。例如:

declare @orderby varchar(10)

set @orderby = 'NAME'

select * 
    from Users
    ORDER BY 
        CASE @orderby
            WHEN 'NAME' THEN LastName
            WHEN 'EMAIL' THEN EmailAddress
        END

这里有一些未记录的命令:未记录但很方便的SQL server Procs和DBCC命令

使用EncryptByKey进行简单加密

/*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