ArcSDE direct connect

ArcSDE Direct Connect, also called a two-tier connect is a method of connecting directly to a ArcSDE Geodatabase without using an ArcSDE application server. This only involves a two-tier configuration, in which the client application directly communicates with the database. ArcSDE License is required for a Direct Connect even though the Client is directly communicating with the Database.


 * ArcSDE Direct Connects utilise the resources from the Client machine for processing and there by reduce load on the Server. In environments where Client machines have good resources and Servers are heavily accessed with Application Server Connections, Direct Connects become an obvious choice.


 * Administering a Direct Connect is not so easy for an ArcSDE administrator. Since this type of Connection does not go through the ArcSDE Service, disconnecting it is a tedious process. It can be easily disconnected either at the Client machine or by restarting a Database service which is not often an option.

Setting up a Direct Connect
Client machines need to be configured based on the Geodatabase being connected to. Steps to follow in setting up a Client machine to connect directly to an ArcSDE geodatabase on each supported database management system (DBMS) are:

Oracle
Configuring a Direct Connect for Oracle DBMS needs installation of Oracle Client and configuring a Netservice name locally on the Client machine, the tnsnames.ora file be altered on the client, and an ODBC connection created.

SQL Server
As long as the Client machine is up-to-date with the Microsoft Data Access Components (MDAC) components and the OLE DB Drivers for SQL Server no additional configuration is required. However, if the Client OS is not up-to-date installing the SQL Server Native Client installs the necessary components.