When you perform a database query in REALbasic you use the SQLSelect
function of the database class. This function returns a databasecursor
which
contains a pointer to the current record (the first record in the
cursor by
default). The databasecursor class also has two boolean properties that
help
you determine if the current record pointer is before the first record
or
beyond the last record. They are called BOF (for Beginning Of File) and
EOF
(for End Of File). You can use these to easily determine if your query
has
found any records.
If your query finds no records, both BOF and EOF will both be true
since the
current record pointer points at nothing.
If your query finds one or more records, both BOF and EOF will be false
since the current record pointer is pointing at the first record and
not at
the beginning or end of the file. For example, if your query found three
records, the cursor would look like this:
BOF
Record1 (the current record pointer is pointing at this record)
Record2
Record3
EOF
--
Geoff Perlman
President & CEO
REAL Software, Inc.
http://www.realsoftware.com
mailto:geoff at realsoftware dot com
Phone: 512-263-1233 x711
Fax: 512-263-1441
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