When rows are added to or deleted from a table, all indexes created for the table are updated. Therefore, as the number of indexes increases, the overhead for index updating increases. Thus, the following considerations should be taken into account when indexes are created:

• Do not define an index for a column that is updated frequently.
• Create multicolumn indexes to reduce the number of indexes.
• In the case of a HiRDB parallel server configuration, create the minimum number of indexes required in order to improve the effects of parallel processing, especially when retrieving all entries.