Generated Sequential Access Method

Generalized Sequential Access Method

Generalized Servicing Access Method

Generalized Sequential Authendication Method

unordered and non hierarchical data base

sequential and hierarchical data base

sequential and non hierarchical data base

unordered and hierarchical data base

Queries

Function calls

DL/I calls

DL/1 calls

CALL 'CBLTDLI' USING call-func, pcb-name, ioarea

CALL 'CBLTDLI' USING call-func, Ioarea

CALL 'CBLTDLI' USING pcb-name, Ioarea

CALL 'CBLTDLI' USING call-func, pdb-name pcb-name, Ioarea

GNXT

GN

GETNEXT

GETN

INSERT

INSRT

ISRT

INST

At the beginning only

At the specified position

At random position

At the end only

True

False

add and edit the record

Add and delete the record

Modify and delete the record

insert and delete the record

Only fixed length record

only variable length record

both fixed length and variable length records

only specified length record

True

False

last 2 bytes of the record

First 2 bytes of the records

3rd and 4th bytes of the record

The record length will not be specified in the record

the data begins in byte 1

the data begins in byte 0

control character in byte 0 and data begins in byte 1

control character is specified at the end

0

GB

Blank

AF

AF

AH

AI

AO

AF

AH

AI

AO

AJ

AI

AH

AO

the data begins in byte 1

byte 0 and byte 1 contains 2 byte length field

byte 0 contains control character and byte 1 and 2 contains the length field

byte 0 and 1 contains the 2 byte length field and byte 3 contains control character

Actual record

Address of the next record

Address of the record retrieved

Address of the previous record

AI

AJ

AM

AH