Distributed Relational Database Architecture (DRDA) communications
DRDA is a set of protocols that enables multiple database systems and application programs to work together.
This section contains information about how to configure IBM® Informix® to use the Distributed Relational Database Architecture™ (DRDA).
- Overview of DRDA
Distributed Relational Database Architecture (DRDA) is a set of protocols that enable communication between applications and database systems on disparate platforms, and enables relational data to be distributed among multiple platforms. - Configuring connectivity between Informix database servers and IBM Data Server clients
To connect to Informix with an IBM Data Server client, you must follow certain configuration steps. - Allocating poll threads for an interface/protocol combination with the NETTYPE configuration parameter
The NETTYPE configuration parameter configures poll threads for each connection type that your instance of the database server supports. You can use this configuration parameter to allocate more than one poll thread for an interface/protocol combination. - Specify the size of the DRDA communication buffer with the DRDA_COMMBUFFSIZE configuration parameter
Use the DRDA_COMMBUFFSIZE configuration parameter to specify the size of the DRDA communications buffer. The minimum size is 4 KB, the maximum size is 2 megabytes, and the default value is 32 KB. - The DRDAEXEC thread and queries from clients
For every DRDA client, IBM Informix creates a session and a DRDAEXEC thread, which is the equivalent of an SQLEXEC thread, to process and run the queries. This thread also formats the results of the queries in the DRDA protocol format and sends the results back to the client computer. - SQL and supported and unsupported data types
When using DRDA, IBM Informix syntax is supported over the common API. When using DRDA connections, Informix rounds decimal and money values to 32-digit precision for all data retrieval operations on decimal or money data types. - Display DRDA connection information
Use onstat and onmode commands to display information that includes the DRDA thread name and an indicator that distinguishes SQLI and DRDA sessions - Display DRDA session information
Use the syssesappinfo table in the sysmaster database to view DRDA client session information.
Parent topic: Client/server communication