Runaway Memory Utilization with NVL function on AIX - IDS 7.30.UC

Has anyone encountered severe performance problems and runaway growth in virtual storage requirements when using the NVL function with a DECIMAL column? SELECT NVL(column_name,0.00) .... where column_name is defined as decimal(8,2) When I use this function in a SELECT statement that retrieves 60,000 rows, it runs for 2 hours and exceeds available virtual memory (>700 MB). If I remove the NVL function or code CASE statements to handle null values in a similar fashion, the query completes in 10 seconds and virtual storage usage is under 100-Kbytes. No problems are encountered when I use this function with an integer column. Our environment is IDS 7.30.UC6-1 running on IBM,7025-F50 (AIX). Rick Rick Bernstein Principal Database Administrator Alaris Medical Systems rbernste@alarismed.com