Access Method Services (AMS)

• Now since you know important concepts of VSAM, Let’s get into how practically that can be implemented using AMS
• Access Method Services – AMS is a powerful service program. It is be used to perform various function on VSAM and non-VSAM datasets
• IDCAMS is the most popular utility provided for AMS
• There are two types of Access Method Services commands:-
  • Functional commands: - Used to request actual work. For example, Defining, Altering, Deleting a dataset or listing a catalog information
  • Modal commands: - Used to specify conditions for execution of functional commands. For example, “IF-THEN-ELSE”. TSO users can use only functional commands