| ESDS |
KSDS | Fixed-length RRDS |
Variable-length RRDS |
Linear data sets |
| Records are in the same order as they are entered |
Records are in Collating sequence by key field after load |
Records are in relative record number order |
Records are in relative record number order |
No processing at record |
| Records can be fixed or variable length |
Records can be fixed or variable length |
Records have fixed length |
Records have variable length |
No processing at record level |
| Direct access by RBA |
Direct access by key or by RBA |
Direct access by relative record number |
Direct access by relative record number |
Access with Data-In-Virtual (DIV) optionally |
| Consist of data component only |
Consist of data and index components |
Consist of data component only |
Consist of data and index components |
Consist of data component only |
| Alternate index allowed |
Alternate indexes allowed |
No alternate index allowed |
No alternate index allowed |
No alternate index allowed |
| A record’s RBA cannot change |
A record’s RBA can change |
A record’s relative record number cannot change |
A record’s relative record number cannot change |
No processing at record level |
| Space at the end of the data set is used for adding records |
Free space is used for inserting and lengthening records |
Empty slots is in the data set are used for adding records |
Free space is used for inserting and lengthening records |
No processing at record level |
| A record cannot be deleted, but you can reuse its space for a record of the same length |
Space given up by a deleted or shortened record becomes free space |
A slot given up by a deleted record can be reused |
Space given up by a deleted or shortened record becomes free space |
No processing at record level |
| Spanned records allowed |
Spanned records allowed |
No spanned records |
No spanned records |
No spanned records |
| Extended format allowed |
Extended format or compression allowed |
Extended format allowed |
Extended format allowed |
Extended format allowed |
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