HP System Dictionary/XL General Reference Manual Vol 1 (32256-90004)

7- 102
capacity: 101;
name: DATE-MAST,automatic;
entry: DATE(2);
capacity: 101;
name: SALES, detail (2/1);
entry: ACCOUNT(CUSTOMER(PURCH-DATE,DELIV-DATE)),
TOTAL,
PURCH-DATE(!DATE-MAST),
DELIV-DATE(DATE-MAST);
capacity: 101;
end.
Figure 7-5. STORE HP IMAGE Database Schema
Data Item
A data item is an ELEMENT entity. The sub-item count, type designator and sub-item length of a data
item is stored in the ELEMENT attributes count, element-type and byte-length, respectively.
Example
To define the data item NAME, create the ELEMENT NAME with the following attributes:
count = 3
element-type = X
byte-length = 30
Data Set
A data set is a IMAGE-DATASET entity. The data set type is stored in the data set attribute image-
dataset-type. A manual master data set has the image-dataset-type MANUAL. An automatic master data
set has the image-dataset-type AUTOMATIC. A relation data set has the image-dataset-type RELATION.
A detail data set has the image-dataset-type DETAIL.
For each data set there should be a RECORD entity occurrence that defines the record layout for that data
set entry. Each ELEMENT (data item) that is in that data set should be related to the RECORD with a
specified byte offset for the relative position of that ELEMENT within that RECORD. The RECORD
should be related to the MANUAL, AUTOMATIC, RELATION, or DETAIL data set entity occurrence that
it describes. This relationship is established with the IMAGE-DATASET contains RECORD relationship
type. Typically, only one record is related to a data set to define a data set entry layout. However, you have
the flexibility of defining more than one record layout for an IMAGE-DATASET entity. Each IMAGE-
DATASET can have one primary record layout which is indicated with the IMAGE-DATASET contains
RECORD relationship type attribute primary-record. To define the DBEFiles associated to a data set, use