the carotenoid content of foods with special reference

Development of database files
It is essential that all information, which is received and found relevant, is entered
into a database structure This allows for easy search and retrieval operations and
permits the data to be manipulated and presented according to user's needs.
The database management system dBASE IV version 15 was used to capture the
data The advantages ot this software package are its ,ide-spread use and availability,
established import and export features for data exchange with other software, and
ability to maniu)Lilate related data files A ti tLie relational databa-e management
system does have some advantages over dBASE IV in terms of the number of
variables and the ability of reltring variables to one anothei However, for the present
purpose, the features of dI3ASL, IV were regarded as sufficient
The data have been entered into three files differing in structure and content, and
referred to as tood.dbl, method.dbf and data.dbf (see Appendix 2 for structure of the
files)
* The file food.dbf contains inrornation on the names, origin and description of
food, The miil t-taceted description en,,ures that each food is Uniq,oly
identified
The file niethod.dbf describes the methods used tor the identification and
quantification of the carotenoids for each food It contains information on
procedures for extraction, saponification, chiomatography and analytical quality
control Modifications of established analytical procedures are flagged and
specified
Fhe file data.dbf contains the data for each carotenoid for all foods. For
practical reasons, it includes some of the information already present in the
food dbf file
The food dbf and data dbt files are linked by a number (foodnr) that uniquely
identifies each food in these files A second link is created by the reference number
(refnr) in the data dbf and method dbf files. Using thee two link fields, the
information from the three data tiles can be co)nbined to produce custom databases
The selection and presentation of the data in Chapter 3 is described in Appendix 3.
Initially, references to sources ot the daui were also entered in dBASE However,
since the program has only linited ability to produce various characters on both
screen and paper, the references (Chapter 7) were entered in WordPerfect format.
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