We currently have a single large database for use in reporting. This contains multiple tables, of which only some are related.
For example, we have 5 tables for one division, 2 tables from another division, etc. Data can flow between divisions, but there is not a structural link between the tables - no foreign key relationships, no duplication of tables. We also have some lookup tables that are used by procedures that populate a lot of the tables in each division - calendar, postcodes, that kind of thing.
Is this best as a single large database, or separated out into smaller databases with thematically linked tables? These tables will grow, and the number of them will increase as new divisions are set up. We will notice any degradation over time, or is this so small as to be insignificant?
Any advice or pointers on things to read are gratefully received.