Master-detail and partitioning takes som considerations. Normally you would partition on a date-dimension. At least if partitioning is used for being able to quickly archive old stuff. But partitioning could be for totally different reasons. For example to spread out data in different filegroups without any actual business meaning in the key. Say you have four disks and put filegroups on each of them, then you could partition by a modulus-operation on an ever-increasing integer-column to spread the data on four disks (eg to avoid hotspots on disk if the table is for a frequently written to log-table).
But let's assume you will partition on a business key like a date column. Then normally you have that column on the master table. If that's the case, and you want to details table to align with the master table, you would have to duplicate the date key down to the details tables.
Quite often, partitioning requires to also alter existing table schema, not just the clustering key of the table.
In order to make suggestions, you'll have to reveal some more information about your tables and your requirements than "I have a details table and two master tables". What purpose do you have with partitioning the tables? What business keys do you already have in the tables?
answered Feb 14 at 08:56 AM