SDE三种连接方式

一、Application server connection

• Traditional ArcSDE connection method
• Server requires ArcSDE service

      1、giomgr listens for client connection requests

      2、gsrvr is spawned for every connection

• Performance considerations

      1、Decreases client load

      2、Increases server load

• Role Of ArcSDE:gsrvr

 

Application server connection life cycle

1、Client requests connection

     giomgr listening on assigned port

2、giomgr spawns dedicated gsrvr

     Connects to Oracle with user name/password supplied by client

3、gsrve services all client Read/Write requests

4、Client closes connection

     gsrvr process terminates

 

二、Direct connect

 

1、Connect directly to database

 

2、No ArcSDE service required

     No giomgr or gsrvr process

     Software included with ArcGis client

 

3、Requires Oracle Net software

     Installed and configured on client

     Oracle listener brokers connections

 

4、Performance considerations

     Increases client load

     Decreases server load

 

5、Role of ArcSDE:direct connect DLL

 

三、Create OLE DB connections

 

1、Industry-standard,COM-based data access interface

     Next generation ODBC

 

2、Two providers for Oracle available with ArcGIS clients

     Oracle:Distributed with Oracle client

     Microsoft:Distributed with MDAC

 

3、Typically Read-only,non-spatial

     ArcObjects programmers can use Read/Write

     ArcGis includes ESRI spatially-enabled provider for programmers