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When reading sequentially, the &NDBGET verb lets you specify the direction of retrieval, FWD or BWD, and a skip amount.
The default is DIR=FWD and SKIP=+1, which causes the next-higher key record to be read.
SKIP=0 causes a re-read of the last record read in that sequence. This is useful where you are retrieving only a subset of fields, and sometimes need to obtain extra fields. You need not specify a direct get by RID.
A skip amount (n) greater than 1 will allow you to skip n-1 records on each &NDBGET. This is extremely useful when extracting samples from a database, and especially useful when scrolling in selection lists (see the following examples).
A negative skip amount causes the specified or defaulted direction to be inverted. For example, SKIP=-5 is equivalent to SKIP=5 with DIR=BWD.
Specifying DIR=BWD allows a backward read to be performed. Thus, when you need to retrieve records in descending key sequence, DIR=BWD can be used.
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