IMS DB – Cobol Basics
We include DL/I calls inside COBOL application program to communicate with IMS database. We use the following DL/I statements in COBOL program to access the database − Entry StatementGoback StatementCall…
IMS DB – Programming
An application program which includes DL/I calls cannot execute directly. Instead, a JCL is required to trigger the IMS DL/I batch module. The batch initialization module in IMS is DFSRRC00. The application…
IMS DB – Control Blocks
IMS Control Blocks define the structure of the IMS database and a program's access to them. The following diagram shows the structure of IMS control blocks. DL/I uses the following…
IMS DB – DL/I Processing
IMS DB stores data at different levels. Data is retrieved and inserted by issuing DL/I calls from an application program. We will discuss about DL/I calls in detail in the…
IMS DB – DL/I Terminology
Hierarchical databases work on the relationships between two or more segments. The following example shows how segments are related to each other in the IMS database structure. Root Segment Points…
IMS DB – Structure
Hierarchical Structure An IMS database is a collection of data accommodating physical files. In a hierarchical database, the topmost level contains the general information about the entity. As we proceed…
IMS DB – Home
IMS stands for Information Management System. IMS was developed by IBM with Rockwell and Caterpillar in year 1966 for the Apollo program to send a man to the moon. It…