RevMedia

A reader called recently to ask for an explanation of the %FIELDS% record found in the dictionary of all files. This record (maintained automatically by DICT.MFS) is documented below. %FIELDS% contains all of the information relating to the dictionary items in a file in one place.

%FIELDS% has 14 fields, all (except for the first two) being associated multi-values controlled by field 3 (the dictionary item names). The record structure is as follows

     < 1 >     Null
     < 2 >     Next field number used when creating new dictionary items.
     < 3 >     Ascending left justified list of all dictionary field names
     < 4 >     Field Type (F, S or G)
     < 5 >     Field Number (blank for symbolic/group)
     < 6 >     Whether field is BTREEd (1) or not (0)
     < 7 >     Whether field is XREFed (1) or not (0)
     < 8 >     Part number if field is part of a multi-parted key
     < 9 >     Flag indicating whether field is multi-valued (1) or not (0)
     < 10 >    Justfication
     < 11 >    Length
     < 12 >    Conversion
     < 13 >    Default value to be used for SQL updates to column
     < 14 >    "Master" flag for bonded files. See E3.12 in AREV 2.0 docs

%FIELDS% can be used to good effect in providing users with rapid access to their dictionary file structure. All that is required is a simple F type popup, pointing to %FIELDS%, field 3.

System Labelled Common

There is a system labelled common area called %F% which contains the %FIELDS% record for the dictionary file last accessed. It seems to be loaded when a dictionary file is opened for the first time after an attach.