Research of mapping XML to non first normal form

Edgar F. Codd, the inventor of the relational model, introduced the concept of normalization and what we now know as the First Normal Form (1 NF) in 1970. Codd went on to define the Second Normal Form (2 NF) and Third Normal Form (3 NF) in 1971, and Codd and Raymond F. Boyce defined the Boyce-Codd Normal Form (BCNF) in 1974. Informally, a relational database table is often described as “normalized” if it is in the Third Normal Form. Most 3 NF tables are free of insertion, update, and deletion anomalies.