What are delta tables?
Versioned editing preserves changes made by all users in two delta tables per table. Each multiversioned table has its own supporting delta tables, which are owned by the same DBMS user that owns the original object. All edits to a multiversioned table are recorded in the same delta tables, regardless of which user makes the edit. One delta table is called the adds table, and the other is the deletes table. The names of these tables begin with either an ‘A’ or ‘D’, respectively, and are often called the A-table and D-table for short. As its name implies, the Adds table stores new rows inserted into the multiversioned table, as well as updated copies of existing rows. Likewise, the Deletes table stores references to old rows deleted from the multiversioned table.
