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

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

其他回答

/*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

在SQL Server 2005中,您不再需要运行sp-blocker-pss80存储过程。相反,你可以这样做:

exec sp_configure 'show advanced options', 1;
reconfigure;
go
exec sp_configure 'blocked process threshold', 30;
reconfigure; 

然后,您可以启动SQL跟踪,并在“错误和警告”组中选择“阻塞”流程报告事件类。详情请点击这里。

找出最流行的查询

与系统。Dm_exec_query_stats,您可以通过一个查询计算出许多查询分析的组合。

链接 用命令

select * from sys.dm_exec_query_stats 
order by execution_count desc

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。

强制参数化

参数化允许SQL Server利用查询计划重用,并避免后续执行类似查询时的编译和优化开销。然而,由于这样或那样的原因,仍然有许多应用程序存在特殊的查询编译开销。对于查询编译次数较多、降低CPU利用率和响应时间对工作负载至关重要的情况,强制参数化可以提供帮助。

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