Updating relational databases through views (complements, mappings, select, project, join)
Arthur M. Keller · 1985
We consider the problem of updating databases through views composed of selections, projections, and joins applied to Boyce-Codd Normal Form relations. The updates are expressed against the view and they must be translated into updates expressed against the database. We present and justify five criteria that these translations must satisfy. For each type of view update (insert, delete, replace), we provide a list of templates for translation into database updates that satisfy the five criteria. We show that there cannot be any other translations that satisfy the five criteria. A translator can be chosen at view definition time by asking the definer of the view a series of questions based on the view definition and database schema. We conclude that it is practical to update relational databases through views for a large class of views by choosing a view update translator at view definition time.