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Which is an example of denormalization in a database?
Thanks to denormalization, only a query on the User_messages table is required to enable a user to select all messages belonging to a specific category. Of course, this denormalization technique has a downside − this extra column may require a lot of storage space.
What’s the difference between denormalization and normalization?
As the name suggests, denormalization is the opposite of normalization. When you normalize a database, you organize data to ensure integrity and eliminate redundancies. Database denormalization means you deliberately put the same data in several places, thus increasing redundancy. “Why denormalize a database at all?” you may ask.
How to avoid a table join in denormalization?
We can avoid a table join by denormalizing the Messages table through adding the first_attachment_name column. Naturally, if a message contains more than one attachment, only the first attachment will be taken from the Messages table while other attachments will be stored in a separate Attachments table and, therefore, will require table joins.
When do you need to use denormalization for attachments?
Naturally, if a message contains more than one attachment, only the first attachment will be taken from the Messages table while other attachments will be stored in a separate Attachments table and, therefore, will require table joins. In most cases, however, this denormalization technique will be really helpful.
Why do you need to normalize the structure of a database?
Before diving into the subject, let’s emphasize that normalization still remains the starting point, meaning that you should first of all normalize a database’s structure. The essence of normalization is to put each piece of data in its appropriate place; this ensures data integrity and facilitates updating.
Which is the opposite of normalization in a database?
And that’s when you can consider denormalizing a relational database. As the name suggests, denormalization is the opposite of normalization. When you normalize a database, you organize data to ensure integrity and eliminate redundancies.