Access/MSSQL/Oracle/MySql获取当前用户连接数

Access/MSSQL/Oracle/MySql获取当前用户连接数

【转】 http://hi.baidu.com/lyybn/blog/item/b1b1ab17c3f629064a90a7ae.html

http://blog.csdn.net/downmoon/archive/2009/01/05/3712313.aspx

一、ＭＳＳＱＬ中可以用sp_Who获取连接的用户名信息，

二、Oracle也有类似的系统函数

Code

SQL> select count(*) from v$session   #连接数

SQL> Select count(*) from v$session where status='ACTIVE'　#并发连接数

SQL> show parameter processes   #最大连接

SQL> alter system set processes = value scope = spfile;重启数据库   #修改连接

三、Access下有以下几种思路：

　　第一：直接看ldb文件，有几行就有几个连接

格式基本上是

　　　　hostname workgroupUserId

　　第二： 用vbscript

　　　　有两段代码可以参考：

　　　　Microsoft:

VBScript

Sub ShowUserRosterMultipleUsers()

Dim cn As New ADODB.Connection

Dim rs As New ADODB.Recordset

Dim i, j As Long

Set cn = CurrentProject.Connection

' The user roster is exposed as a provider-specific schema rowset

' in the Jet 4.0 OLE DB provider.   You have to use a GUID to

' reference the schema, as provider-specific schemas are not

' listed in ADO's type library for schema rowsets

Set rs = cn.OpenSchema(adSchemaProviderSpecific, _

, "{947bb102-5d43-11d1-bdbf-00c04fb92675}")

'Output the list of all users in the current database.

Debug.Print rs.Fields(0).Name, "", rs.Fields(1).Name, _

While Not rs.EOF

Debug.Print rs.Fields(0), rs.Fields(1), _

rs.Fields (2), rs.Fields(3)

rs.MoveNext

Wend

End Sub

　　　Access Web:

VBScriptCode

' This code was originally written by Dev Ashish.

' It is not to be altered or distributed,

' except as part of an application.

' You are free to use it in any application,

' provided the copyright notice is left unchanged.

'

' Code Courtesy of

' Dev Ashish

'

Private Declare Function apiGetUserName Lib "advapi32.dll" Alias _

Function fOSUserName() As String

' Returns the network login name

Dim lngLen As Long, lngX As Long

Dim strUserName As String

strUserName = String$(254, 0)

lngLen = 255

lngX = apiGetUserName(strUserName, lngLen)

If (lngX > 0) Then

fOSUserName = Left$(strUserName, lngLen - 1)

Else

fOSUserName = vbNullString

End If

End Function

'******************** Code End **************************

四、MySql

mysql >     show    processlist;

或

Code

./mysqladmin    processlist  

例：

C:/Documents and Settings/administrator>mysqladmin processlist

更详细的，查看当前所有连接的详细资料:

./mysqladmin -uadmin -p -h10.140.1.1 processlist

只查看当前连接数(Threads就是连接数.):

./mysqladmin   -uadmin -p -h10.140.1.1 status