4.3 FIELD DEFINITION TABLE (FDT)
The FDT defines the fields that may be present in the database and certain parameters for each field. You enter the values in the boxes at the top of the dialog box. In the DOS version, the FDT had little effect – you could repeat a field or enter subfields regardless of what the FDT said. The Windows version is much stricter and you need to be more careful about your definition (although you can always change it later).
The boxes are as follows:
(a) Tag -- see above. You can use the up and down arrows if you like to select the number, or type it in.
(b) Name -- this is to help you identify the field. It can be up to 31 characters long and can contain spaces. When you come to set up the data entry worksheet, this name will be used as
the prompt for the field, but you can override it there. It is also used to
specify the field in the “Guided Search” form.
(d) Type. Unless you can predict that the field will contain only letters (no spaces or punctuation) or only figures (no symbols or decimal point) it is
best to leave this as Alphanumeric. The other possible values are Alphabetic or
Numeric. The beginner is strongly advised to use Alphanumeric.
(e) Rep[eatable]. If you want to allow multiple occurrences of this field, e.g. several authors or several descriptors, click this checkbox.
(f) Pattern/subfields. If you are dividing the field into subfields, you should list the subfields here (without punctuation or spaces) e.g.
abc
If you are not using subfields, press the ( key to leave this box blank. Pattern fields are not supported in Version 1.4.
When you have entered the data for each field, the focus will be on the Add button. Either click the button or press {Enter} to add the field to the table (displayed in the large box). If you need to correct the details for any field, just click on that entry in the large box and the details will be copied into the boxes used for editing. If you need to remove an entry, highlight it and click the Delete Entry button. You can alter the order of fields by selecting a field and clicking the up-arrow or down- arrow key: they do not have to be in numeric order, though
that is usually clearest. An example of an FDT is shown in Figure 4.1.
Figure 4.1 Example of a Field Definition Table (FDT)
After entering all the fields, click the button with the green arrow to go on.
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