How does TOYS compare schemas?
TOYS uses a very simple concept of operating on meta-data “snapshots”. These snapshots are meta-data extracted from the database catalogs at a point in time. TOYS reads (or captures) meta-data from the database catalogs and constructs an in-memory model of the database structure. This is referred to as a “snapshot” and is analagous to a photographic snapshot in that it is a “picture” of the database structure at some point in time. These snapshots contain all the relevant meta-data describing the schemas that you nominated. In order to compare two databases you first have to capture a snapshot of each of them. Thus you can connect to two different [physical] databases and capture your meta-data snapshots. Alternatively, you can capture both snapshots from the same [physical] database. In this second senario, the nominated schema names will be different. As a third alternative, TOYS allows you to save a snapshot to a file [as XML] and to reload this snapshot file at a later time. When c
