MAINFRAMES....

Entry sequential Data Set(ESDS)

Features-

       

1)      It is just like a PS file .

2)      It has only data component no Index component.

3)      No keys field like KSDS file.

4)      ESDS file access can be sequential or random but not dependent on primary key.

5)      There is no any free space in ESDS file.

Below is program for creation of ESDS VSAM file.



  //E114298J JOB ,,NOTIFY=&SYSUID,CLASS=B
  //STEP1 EXEC PGM=IDCAMS                                          
  //SYSPRINT DD SYSOUT=*                                           
  //SYSIN DD *                                                     
       DEFINE CLUSTER(NAME(E114298.ESDS.VSAM)   -                
       NONINDEXED                               -                
       RECSZ(80,80)                             -                 
       TRACKS(1,1)                              -                
       CISZ or control interval size(4096)   
/*
//



Control interval size is multiple of 4096 bytes upto 32 k.

The fields in the control card is not positional you can write it in any position.


So now I will write my ESDS file creation program.

               


 
Output of above JCL is

So cluster and data file will be created.

The delete program is same as KSDS delete program.

Here after deleting the cluster ESDS file and data file both will get deleted.

Loading of Data in Vsam file


There is no any ascending insertion rule in ESDS file system . you can insert a data as you want like normal ps file.