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

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())

其他回答

不是无证

行号由Itzik Ben-Gan 提供 http://www.sqlmag.com/article/articleid/97675/sql_server_blog_97675.html

设置xact_abort为on 在事务发生错误时回滚所有内容

所有的sp_都很有帮助,只是在网上浏览书籍

我在管理工作室一直使用的快捷键 F6 -结果和查询之间切换 Alt+X或F5-在查询中运行选中的文本,如果没有选中则运行整个窗口 Alt+T和Alt+D -结果在文本或网格分别

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

好吧,这是我的观点:

http://dbalink.wordpress.com/2008/10/24/querying-the-object-catalog-and-information-schema-views/

我懒得在这里重新写一遍,所以请查看我的帖子。这对许多人来说可能是微不足道的,但会有一些人会发现它是一颗“隐藏的宝石”。

编辑:

过了一会儿,我决定在这里添加代码,这样您就不必跳转到我的博客来查看代码了。

SELECT  T.NAME AS [TABLE NAME], C.NAME AS [COLUMN NAME], P.NAME AS [DATA TYPE], P.MAX_LENGTH AS[SIZE],   CAST(P.PRECISION AS VARCHAR) +‘/’+ CAST(P.SCALE AS VARCHAR) AS [PRECISION/SCALE]
FROM ADVENTUREWORKS.SYS.OBJECTS AS T
JOIN ADVENTUREWORKS.SYS.COLUMNS AS C
ON T.OBJECT_ID=C.OBJECT_ID
JOIN ADVENTUREWORKS.SYS.TYPES AS P
ON C.SYSTEM_TYPE_ID=P.SYSTEM_TYPE_ID
WHERE T.TYPE_DESC=‘USER_TABLE’;

或者,如果你想拉出所有的用户表,像这样使用CURSOR:

DECLARE @tablename VARCHAR(60)

DECLARE cursor_tablenames CURSOR FOR
SELECT name FROM AdventureWorks.sys.tables

OPEN cursor_tablenames
FETCH NEXT FROM cursor_tablenames INTO @tablename

WHILE @@FETCH_STATUS = 0
BEGIN

SELECT  t.name AS [TABLE Name], c.name AS [COLUMN Name], p.name AS [DATA Type], p.max_length AS[SIZE],   CAST(p.PRECISION AS VARCHAR) +‘/’+ CAST(p.scale AS VARCHAR) AS [PRECISION/Scale]
FROM AdventureWorks.sys.objects AS t
JOIN AdventureWorks.sys.columns AS c
ON t.OBJECT_ID=c.OBJECT_ID
JOIN AdventureWorks.sys.types AS p
ON c.system_type_id=p.system_type_id
WHERE t.name = @tablename
AND t.type_desc=‘USER_TABLE’
ORDER BY t.name ASC

FETCH NEXT FROM cursor_tablenames INTO @tablename
END

CLOSE cursor_tablenames
DEALLOCATE cursor_tablenames

其他参考资料(我的博客):http://dbalink.wordpress.com/2009/01/21/how-to-create-cursor-in-tsql/

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。

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