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