Syllabus Detail
- Data duplication. 12 ATAR
- Data redundancy. 11 ATAR, 12 GEN, 12 ATAR
Background
- Data duplication and data redundancy are similar concepts, but are not the same
- Both concepts work to ensure efficiency and consistency in terms of databases and storage
Data Redundancy
- Data redundancy occurs when the same data is entered in to two or more fields of a database
- For example, "Joe" is entered in to the Name field under a record called Customers
- "Joe" is also entered in to the Customer field under a record called Purchases
- Although we are referring to the same Joe in both fields, each piece of data is seen as unique
- This means that to update "Joe", we need to manually edit each reference
- This can cause problems in database systems such as data anomalies
- This differs from data duplication, as it is often not intentional and can take up potentially required storage space
Data Duplication
- Data duplication occurs when an exact copy of a piece of data is created
- For example, copy and pasting an item called "MyPicture.jpg"
- The new pasted item contains the exact same data as the original picture
- On different Operating Systems, the naming convention for copies will change (e.g. "MyPicture 2.jpg" or "MyPicture copy.jpg")
- Data duplication provides benefits such as providing us with the ability to back up copies of files and create multiple verions of a file (which may be required for progress reporting or other information)
- The duplication of data is often intentional and used primarily for creating backups
- Data duplication on a database may result in data redundancy, and thus an inefficient and inconsistant database
Why are these important?
- The act of normalising a database (organizing data to prevent redundancy) is critical to maintain an efficient and clean database
- Ensuring unncessary data doesn't reside on the database allows for a consistent and accurate database
- The ability to duplicate data intentionally allows us to create backups and maintain our data
Further Research
- Read more about Data Redundancy from DatabaseDev here
- Read more about Data Duplication from GeekInterview here
Found an error or have an enhancement? Please let us know via this contact form