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

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。

Link

其他回答

主. .Spt_values(特别是type='p')对于字符串分割和执行'bin '和时间插值操作非常有用。

一个不太为人所知的TSQL技术,以随机顺序返回行:

-- Return rows in a random order
SELECT 
    SomeColumn 
FROM 
    SomeTable
ORDER BY 
    CHECKSUM(NEWID())

使用EncryptByKey进行简单加密

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。

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。