| 摘要 |
<p>A system and method selects rows from a fact table (100) in a dimensional database also containing a time dimension table (110) and other dimension tables (120, 130, 140). The other dimension tables each contain rows (122, 132, 142) containing a time invariant attribute to identify an item described by the row, an effective time attribute for the row, and other attributes. If an attribute for an item changes, a new row is added to the dimension table containing the time-invariant attribute for the item and current attributes for the item, without deleting or overwriting any existing rows for that item. One of the dimension tables (120, 130, 140) can be selected to create other tables using the time attributes existing in the dimension table. One of the resulting tables are then joined to a table in the dimensional database.</p> |
