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

好吧,这是我剩下的一些,很遗憾我错过了开始,但继续吧,这里有一些顶级的东西!

查询分析器

Alt+F1对所选文本执行sp_help Alt-D -聚焦到数据库下拉菜单,这样你就可以使用字母光标键选择db。

t - sql

if (object_id("nameofobject") IS NOT NULL) begin <do something> end -最简单的存在性检查 Sp_locks——比sp_who2(这是第一个调用端口)更深入的锁定信息 DBCC inputbuffer(spid) -执行进程的顶部行列表(有点有用,但简单) DBCC outputbuffer(spid) -执行进程输出的顶行列表

通用T-sql技巧

对于大容量的数据,可以自由地使用子查询来处理集合中的数据

例如,获得已婚人士的名单 50岁以上的人可以选择 一群结婚的人 子查询并与一组 同样是50岁以上的人 加入结果-请原谅 的例子

其他回答

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

以下是一些我认为有用但很多人似乎不知道的功能:

sp_tables

返回可以为的对象列表 在当前环境下查询。 这意味着任何对象都可以出现 在FROM子句中,同义词除外 对象。

Link

sp_stored_procedures

中存储过程的列表 当前环境。

Link

Persisted-computed-columns

计算列可以帮助您将运行时计算成本转移到数据修改阶段。计算列与行其余部分一起存储,当计算列上的表达式与查询匹配时,将透明地使用它。您还可以在PCC上构建索引,以加快表达式的过滤和范围扫描。

Link

我发现sp_depends很有用。它显示依赖于给定对象的对象,例如。

exec sp_depends 'fn_myFunction' 

返回依赖于此函数的对象(注意,如果对象最初没有按照正确的顺序运行到数据库中,将会给出错误的结果。)

删除到数据库的所有连接:

Use Master
Go

Declare @dbname sysname

Set @dbname = 'name of database you want to drop connections from'

Declare @spid int
Select @spid = min(spid) from master.dbo.sysprocesses
where dbid = db_id(@dbname)
While @spid Is Not Null
Begin
        Execute ('Kill ' + @spid)
        Select @spid = min(spid) from master.dbo.sysprocesses
        where dbid = db_id(@dbname) and spid > @spid
End