Home
Client APIs and toolsYou can use the HCL OneDB™ implementation of client APIs to develop applications for HCL OneDB™ database servers.
ESQL/C GuideThe HCL OneDB™ ESQL/C Programmer's Manual explains how to use , the HCL OneDB™ implementation of Embedded Structured Query Language (SQL) for C (ESQL/C), to create client applications with database-management capabilities.
Database server communication
Working with the database serverThese topics explain how the HCL® OneDB® ESQL/C program can interact with a database server.
The client-server connectionThe application can establish a connection to any valid database environment. A database environment can be a database, a database server, or a database and a database server.
Identify the database server

Identify the database server

To connect to a database environment (with, for example, a CONNECT statement), the application can identify the database server in one of two ways:

The application can specify the name of the database server in the SQL statement. Such a database server is a specific database server.
The application can omit the name of the database server in the SQL statement. Such a database server is the default database server. The INFORMIXSERVER environment variable specifies the name of the default database server.