Inserting physically and logically deleted segments
When a segment is inserted, a replace operation is performed (space is reused), and existing dependents of the inserted segment remain if certain conditions are met.
A replace operation is performed (space is reused) and existing
dependents of an inserted segment remain when a segment is inserted
if:
- The segment to be inserted already exists (same segment type and same key field value for both the physical and logical sequencing)
- The delete bit is set on for that segment along the path of insertion
For HDAM and HIDAM databases, the logical twin chain is established as required, and existing dependents of the inserted segment remain.
For HISAM databases, if the root segment is physically and logically deleted before the insert is done, then the first logical record for that root in primary and secondary data set groups is reused. Remaining logical records on any OSAM chain are dropped.