The CCINFO structure resides in the memory space of the client or the DDF address space (depending on the configuration). It is part of the layer. When an application connects to DB2 using standard APIs (like ODBC or JDBC), the driver creates an environment handle and a connection handle.

Modern enterprise databases rely on distributed architectures where client applications do not interact directly with the storage engine but rather through a series of sophisticated communication layers. In the IBM DB2 ecosystem—specifically within the Call Level Interface (CLI) and the underlying Distributed Data Facility (DDF)—the term CCINFO refers to a specific memory control block (structure).

Internally, these handles are managed via control blocks: