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MSSQL:
declare @begin datetime
declare @End datetime
set @begin=getdate()
--Ö´ÐеÄÓï¾äдÔÚÕâÀï
set @End=getdate()
select datediff(millisecond,@begin,@End) as Ö´ÐеÄʱ¼ä
--millisecond±íʾºÁÃë Èç¹û¿´Ãë¿ÉÒÔʹÓÃss
C#:
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protected void Page_Load(object sender, EventArgs e)
{
Stopwatch watch = new Stopwatch(); //ʵÀý»¯Ò»¸ö¼à¿Ø¶ÔÏó
watch.Start(); //¿ªÊ¼¼à¿ØÒµÎñÂß¼
string a = null;
for (int i = 0; i < 10000; i++)
{
a = i.ToString();
}
Thread.Sleep(10); //½«Ïß³ÌÑÓ³Ù10ºÁÃë¡£Ò»¸ö¶àÕâÑùµÄ²âÊÔ£¬¶àҪʹÓõ½Ï̷߳½Ãæ
watch.Stop(); //½áÊø¼à¿Ø
Response.Write(watch.ElapsedMilliseconds); //Êä³ö¼Æʱ½á¹û£¬µ¥Î»£ººÁÃë
}
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Sql server:select top n * from ±íÃû order by newid()
mysql select * from ±íÃû Order By rand() Limit n
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select top 5 * from (select top 15 * from table order by id asc) table_±ðÃû or ......
declare @tmp table
(
id int identity(1,1),
TableName varchar(100),
Column_name varchar(100),
Type varchar(50),
Lenght int,
Scale int,
Nullable varchar(1),
Defaults varchar(4000),
PrimaryKey varchar(1)
)
select iid = identity(int,1,1), * into #a from SysObjects where xtype = 'U'
declare ......
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CREATE DATABASE database-name
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Create DATABASE database-name
2¡¢ËµÃ÷£ºÉ¾³ýÊý¾Ý¿â
drop database dbname
3¡¢ËµÃ÷£º±¸·Ýsql server
--- ´´½¨ ±¸·ÝÊý¾ÝµÄ device
USE master
EXEC sp_addumpdevice disk, testBack, c:mssql7backupMyNwind_1.dat
--- ¿ªÊ¼ ±¸·Ý
BACKUP DATABASE pubs TO testBack
4¡¢Ë ......