Database normalization is something that is often overlooked when it comes to creating a data quality plan and working with the data. All too often, overworked database administrators simply brush off the thought of normalizing their databases, calling it something that is just a luxury – a task that you might worry about as an academic, but not apply in the ‘real world’. This is a dangerous way of thinking, because it means that your database designs could be flawed, and that the performance of your production environment databases will suffer.
Database normalization basics is something that should be considered from the moment that the database is built. Efficiently organizing data in your database, using proper data mining techniques in CRM and eliminating redundant data will make your database more stable, less error prone, and faster too. Another important element of database normalization is ensuring that your data dependencies always make sense. If you store related data in a haphazard fashion, you run the risk of poor performance, incorrect data being gathered, and data loss.
What Database Normalization Basics Is All About
Database normalization basics is more than just a worthy goal and a good practice – it will make queries easier, and it will reduce the amount of space (storage and RAM) that the database consumes.
There are some very good guidelines for database normalization out there, which offer advice that database engineers can follow to make any database efficient. These guides are presented as ‘normal forms‘ and are numbered 1 through 5 – written 1NF to 5NF. The 1, 2 and 3NF practices are the ones that are seen the most often in the ‘real world’, with four being more rare and number five tending to be a theoretical practice only.
The Normal Form Guidelines
Note that the normal forms are just guidelines, and there will be occasions when you would deviate from them. However, the guidelines exist to make you think about best practices. If you think about them, and know WHY you are breaking them, then that is much better than going into the job with no plan at all.
A good starting point is to plan out the tables that you are going to use. Create separate tables for each group of data, and make sure that there is one primary key – a key that will always be unique.
Remove any subsets of data which can be applied to multiple rows on a table, and put them in a separate table.
Once you have the tables separated in this way, you can create relationships between the new tables and the original ones using foreign keys, and then remove any columns that are not dependent on your primary key, and then you have a database which meets most of the requirements of the third normal form.
If the database relation has no multi-valued dependencies, then this means that it meets the fourth normal form.
Database normalization basics can take a lot of work, but it is usually an easy job with the right data management solutions, so you will be able to use the database in confidence that it is reliable and will run efficiently.