Suppose a file in AS/400 DB2 has 1000 records. How can I retrieve the last 100 rows from the file?
This is an interesting twist on the usual "Top N" query question. There are two parts to the answer. First, you can get the last N simply by running a Top N query which includes an ORDER BY clause with the DESCENDING keyword.
Second, since DB2 is one of the databases which has implemented special syntax just for the purpose of this type of query (others being Microsoft SQL Server and Access with TOP and MySQL and PostgreSQL with LIMIT), you simply utilize that syntax. According to the DB2 Universal Database for iSeries SQL Reference page for the select-statement, this would be
select foo, bar from yourAS400table order by foo descending fetch first 100 rows only
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