ENABLE Reference Manual

INTRODUCTION
Dictionary Files
Dictionary Files
ENABLE accesses DDL data dictionary files to extract information
about the data base files to be used by an application. The
dictionary must contain a record description of each file to be
used. The record description must be compatible with SCREEN
COBOL representation capabilities. Specifically, this means that
the DDL statements and clauses used to create the record
description must conform to the following rules:
• A TYPE clause must be CHARACTER or BINARY.
• OCCURS clause nesting must not exceed four levels; the OCCURS
value (number of occurrences) must not exceed 999.
• Elementary items must not exceed 256 bytes.
• The record must not exceed 2046 bytes. For key-sequenced
files, the record cannot exceed 2035 bytes.
• FILLER and REDEFINES items can appear in a record description;
however, these items do not appear on the screen. The
application displays only named items and the first
declaration of a redefined structure.
• When several fields constitute a record key and have the same
byte offset, only the field at the highest level of the group
is available as a key.
• When an OCCURS DEPENDING ON clause appears, ENABLE uses the
maximum possible record size. If an application reads a
record that is shorter than the maximum length, the General
Server pads the records with blanks. This padding can cause
some problems in numeric fields.
The application uses the maximum record size when writing all
records with OCCURS DEPENDING ON clauses to the data base.
Therefore, if you update a variable-length record that is
shorter than the maximum size, the application writes out a
record that is of the maximum size and ignores the value of
the item upon which the OCCURS depends. For entry-sequenced
files, such an update results in an error.
• BINARY 8, FLOAT 32, FLOAT 64, COMPLEX, LOGICAL 2 and LOGICAL 4
data items are not supported by ENABLE.
• If a HEADING clause appears, ENABLE uses only the first 28
characters of the heading.
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