Notice that the
database has six fields of varying types. Fields 1 and 2 are Character type, 3
is a Date, 4 is Numeric, 5 is Logical, and 6 is a Memo field. The database
files have the extension DBF.
The database
might contain information similar to that shown in the following table.
Record FÍME LNAME DATE RATE ABSENT COMMENTS
1 John Smith 10/12/42 12.50 .F. (Memo)
2 Alice Garica 02/21/68 9.60 .F. (Memo)
3 George Wong 06/05/72 7.75 .F. (Memo)
This table show
the first three records (001 through 003). Notice that the appreance of the
information matches the designated field types, and that each record
corresponds to a different person. This is typical of databases. Usually, a
record is about a unique entity such as a customer, business establishment,
inventory item, or property.
The contents of
each field type must follow certain rules.
Character - A combination of letters, numbers, space,
and/or punctuation marks that are treated as a test string. When a
string is used as part of a command, it is enclosed in single quotes, quotation
marks, or square brackets (‘text’ “text” [text]. If you wish to use one of
these punctuation marks (or delimiters) as part of a string. Enclose the
string with one of the other delimiters.
Example: “Enter student’s name.”
If both a single and double quote are
used within the text of your prompt string, you can use the bracket delimiter.
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