The process to alter the structure of a database is basically categorized into two ways one is Normalization and other is Denormalization.
The following are the important differences between Normalization and Denormalization.
|1||Implementation||Normalization is used to remove redundant data from the database and to store non-redundant and consistent data into it.||Denormalization is used to combine multiple table data into one so that it can be queried quickly.|
|2||Focus||Normalization mainly focuses on clearing the database from unused data and to reduce the data redundancy and inconsistency.||Denormalization on the other hand focus on to achieve the faster execution of the queries through introducing redundancy.|
|3||Number of Tables||During Normalization as data is reduced so a number of tables are deleted from the database hence tables are lesser in number.||On another hand during Denormalization data is integrated into the same database and hence a number of tables to store that data increases in number.|
|4||Memory consumption||Normalization uses optimized memory and hence faster in performance.||On the other hand, Denormalization introduces some sort of wastage of memory.|
|5||Data integrity||Normalization maintains data integrity i.e. any addition or deletion of data from the table will not create any mismatch in the relationship of the tables.||Denormalization does not maintain any data integrity.|
|6||Where to use||Normalization is generally used where number of insert/update/delete operations are performed and joins of those tables are not expensive.||On the other hand Denormalization is used where joins are expensive and frequent query is executed on the tables.|