7.3 Performance with PeopleSoft application

For the PeopleSoft databases, we currently UPDATE STATISTICS MEDIUM on the entire database, then UPDATE STATISTICS HIGH DISTRIBUTIONS ONLY on each column which leads an index, then UPDATE STATISTICS LOW for each additional column referenced in other parts of an index which are not a lead column on another index. In our internal custom database which we run Informix 4GL apps against, we pursue a similar but different strategy. We update statistics medium on each individual table, then update statistics high on columns which lead an index OR we update statistics high on multiple columns in the same order in which they appear in important indexes. I want to know if these strategies are appropriate or are there better strategies to improve performance, particularly on the PeopleSoft databases. Since going to 7.3 the performance of the PeopleSoft databases have improved in some cases but severely degraded in other cases. We have also seen poor performance in our internal custom app which has been fine for years in regards to some joins on unindexed columns. This CASE # is 794304 Opened 11-12-98 Thanks in advance.