Nonstop Database, HiRDB Version 9 UAP Development Guide
When multiple indexes are defined for a table, the HiRDB system usually uses the indexes sequentially, beginning with the one that defines the most efficient condition to narrow the number of retrieved rows. However, depending on the search conditions, the HiRDB system might first use the index it judges to be the most appropriate, regardless of the priority.
There is no need to consider how to retrieve data from a table when creating a UAP. However, to ensure that HiRDB selects the index best suited to the system, define an index for the column for which the search condition is specified.
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