SELECT FROM(BOOKS) TO(PUBLISHR) ON(29,10,CH) FIRST

Sorts the BOOKS data set to the PUBLISHR data set, selecting only the records from BOOKS with characters in positions 29-38 that occur only once and the first record of those with characters in positions 29-38 that occur more than once (that is, one record for each unique ON field value).

The PUBLISHR data set might look as follows (several records are shown for illustrative purposes):

Banana Slugs I Have Known   Brent      Animals
Toads on Parade             Cooper     Animals
Pets Around the World       Davis      Animals
.                           .          .
.                           .          .
.                           .          .