Normalization and normal form an overview

Normalization And Normal Forms is an important concept that forms the basis of RDBMS(Relational database Management System).Normalization is simplification of tables into a progressively simpler formto get rid of undesirable attributes.The undesirable attributes can be data anomalies and duplicate data. First Normal Form - A table is said to be in 1NF if it doesn't contain any repeating groups.To summarize 1) No duplicate rows in the table 2) Each cell is single valued(cell is the intersection of a row and column) 3) Entries in a column are of same kind Second Normal Form - A table is said to be in 2NF if it is already in 1NF and non-key attribute is fully functionally dependent on the primary key. Third Normal Form - A table is said to be in 3NF if it is already in 2NF and every non-key attribute is fully and directly dependent on the primary key.i.e eliminate the columns that arent dependent on the key. Boy-codd Normal Form (BCNF) - It is based on candidate keys.A relation is said to be in BCNF is every determinant is a primary key. Fourth Normal Form - This takes care of multi-valued dependency.It is in 4NF if it is in BCNF and contains no nontrivial multivalued dependencies. Fifth Normal Form - 5NF has no join dependency Transactions in RDBMS possess four important properties. They are popularly referred to as ACID A - Atomicity C - Consistency I - Isolation D - Durability