The INTO option moves the information in the TIOA into the reserved specified area, while the SET option simply returns the address of the TIOA to the specified BLL cell or address of a linkage-section.

The following are the ways of initiating a CICS transaction.

1. By entering Transaction Id

2. By Start command

3. By Return Trans Id (as in pseudo - conversation)

4. By Registering Tran ID in plt so that it will be automaticaly dusring CICS start

5. By ATI (Automatic task initiation)

6.PF & PA keys as defined in PCT

Primary key : a relational database constraint. Primary key consists of one or more columns that uniquely identify a row in the table. For a normalized relation, there is one designated primary key.

Unique index: a physical object that stores only unique values. There can be one or more unique indexes on a table.

 -1 indicates the field is null

 0 indicates the field is not null

 -2 indicates the field is truncated

CURSOR STABILITY:

- CS is a row level locking

- Acquires an exclusive lock on the row that is to be updated

- When the control is moved to the next updatable row, the lock is released

REPEATABLE READ:

- RR is a page level locking

- Acquires an exclusive lock on the entire page which is the source of row availability

- When the control is moved to the next updatable page the lock is released

Static (embedded) SQL:

1.In static SQL how database will be accessed is predetermined in the embedded SQL statement.

2.It is more swift and efficient.

3.SQL statements are compiled at compile time.

4.Parsing, validation, optimization, and generation of application plan are done at compile time.

5.It is generally used for situations where data is distributed uniformly.

6.EXECUTE IMMEDIATE, EXECUTE and PREPARE statements are not used.

7. It is less flexible 

Dynamic (interactive) SQL:

1.In dynamic SQL, how database will be accessed is determined at run time.

2.It is less swift and efficient.

3.SQL statements are compiled at run time.

4.Parsing, validation, optimization, and generation of application plan are done at run time.

5.It is generally used for situations where data is distributed non-uniformly.

6.EXECUTE IMMEDIATE, EXECUTE and PREPARE statements are used.

7.It is more flexible.

A system call is a function.subroutine which interrupts the currently executing program and transfers control to the interrupt routine.The contents of the executing program are saved and after the interrupt routine finishes its function,control is transferred back to the executing program. If we talk in the context of Linux then System calls are called kernel mode.

Whereas API (Application Programming Interface) is a function or a set of functions, objects, protocols or data-structures for the support of application development for developers/programmers. It is actually a kind of function definition which specifies how to make available of a specific service of the system/OS to the other program/process or system. Read more at: https://www.queryhome.com/48442/os-what-is-difference-between-system-call-and-api

The main types of system calls are as follows:

Process Control: These types of system calls are used to control the processes. Some examples are end, abort, load, execute, create process, terminate process etc.

File Management: These types of system calls are used to manage files. Some examples are Create file, delete file, open, close, read, write etc.

Device Management: These types of system calls are used to manage devices. Some examples are Request device, release device, read, write, get device attributes etc.

Information Maintenance: These types of system calls are used to set system data and get process information. Some examples are time, OS parameters, id, time used etc.

Communications: These types of system calls are used to establish a connection. Some examples are send message, received messages, terminate etc