The time dimension is a special dimension that contains information about times. For every possible time that may appear in the fact table, an entry must exist in the time dimension table. This time attribute is the primary key to the time dimension. The non–key attributes are application specific and provide a method for grouping the discrete time values. The groupings can be anything that is of interest to the organization. Some examples might be:
Day of week
Week end
Early closing day
Public holidays/bank holidays
24-hour opening day
Weather conditions
Week of year
Month name
Financial month
Financial quarter
Financial year
Some of the groupings, listed above, could be derived from date manipulation functions supplied by the database management system, whereas others, clearly, cannot.
The time dimension is a special dimension that contains information about times. For every possible time that may appear in the fact table, an entry must exist in the time dimension table. This time attribute is the primary key to the time dimension. The non–key attributes are application specific and provide a method for grouping the discrete time values. The groupings can be anything that is of interest to the organization. Some examples might be:
Day of week
Week end
Early closing day
Public holidays/bank holidays
24-hour opening day
Weather conditions
Week of year
Month name
Financial month
Financial quarter
Financial year
Some of the groupings, listed above, could be derived from date manipulation functions supplied by the database management system, whereas others, clearly, cannot.