bdfm1m16Messages (System Error, Online, Offline) and Master Glossary

L

leaf
Synonym for leaf node.

leaf block
Synonym for leaf node.

leaf node
The lowest-level node. It contains pointers to the data blocks. Synonymous with leaf and leaf block.

logical record (LREC)
The smallest unit of data that a TPFDF program normally accesses (reads, adds, or deletes). An LREC contains several fields, one of which must be the LREC ID. The TPFDF product supports three types of LRECs: fixed-length, variable-length, and extended LRECs.

LREC
Logical record.

LREC ID
A 1-byte field identifying the logical record type. The LREC ID (equated to a value in the file DSECT) is also called the primary key of the LREC.

LREC keys
The TPFDF product allows searches for logical records (LRECs) by comparing program-provided search arguments against specified data fields in the logical record. The search arguments are called search keys. The data fields in the logical record are called logical record (LREC) keys.