The columns on the Time-based dimensions are as below.  In each Data Mart just the columns required are available for retrieval.

On the Data Warehouse this is referred to as Dim_Time.  On the Data Marts it is referred to based upon the time column in the Fact table.

Column Name Data Type Description Derivation
time_sk integer This uniquely identifies the time record. This has no business meaning.
time_hours integer The time in hours, 24 hour clock.  
time_minutes  integer  The minutes associated with the time.   
core_time  varchar  Whether the time is the core/ main business hours.  'YES' for hours 9-17.  Other times set to 'NO'.
library_core_time varchar Whether the time is within the library core time 'YES' for hours 8-23.  Other times set to 'NO'.