| Q | What is a DBD ? |
| A | DBD stands for DATABASE DEFINITION. It is to define segements,key fields and access methods used for an IMS Database. |
| Q | What is a PSB ? |
| A | PSB stands for PROGRAM SPECIFICATION BLOCK.It is made up of one or more pcb's.It also defines the database used by the application program. |
| Q | What is an ACB ? |
| A | ACB stands for APLICATION CONTROL BLOCK.It Contains the information of the PSB with the corresponding DBD information. |
| Q | What is SSA ? |
| A | SSA stands for SEGMENT SEARCH ARGUMENTS which is used to describe which segments to be retrieved. |
| Q | What are the different types of SSA's ? |
| A |
There are 2 types of SSA’S . QUALIFIED SSA: It is used to retrieve a particualar occurence of a segment. UNQUALIFIED SSA: It is used when no particular segment occurence is requested. |
| Q | What is the status code after a successful execuetion of a DL/I call ? |
| A | The status code will have spaces after a successful execuetion of a a DL/1 call. |
| Q | What are the four control blocks of Message Format Service (MFS) ? |
| A |
Message Input Data (MID):Describes the input message as the application program sees it. Message Output Data (MOD):Describes the output message as the application program formats it. Data Input Format (DIF):Describes the screen format for accepting input from the user. Data Output Format (DOF):Describes the screen format as the user sees it. |
| Q | What are the the 3 essential fields required for a DL/I call ? |
| A |
Function Code(GU,GHU,ISRT,REPL...) PCB Mask I/O Area |