A database is an organized collection of data designed to provide efficient retrieval. Prior to 1970, database systems used a flat file to store information. This concept required sequential searching of all records to find information.
Edgar Codd (right) invented the the concept of relational databases in 1970. In the early 1980s, he proposed Codd's 12 Rules, a set of thirteen rules numbered from zero to 12, that describe what is required of a truly relational database. Truly relational databases are highly optimized for performance in retrieval and appending database operations.
Since 2011, the amount of data has grown massively - see The Age of Big Data. 90% of all data, from the beginning of time, as been created in the last two years! This data is not structured - from video, pictures, Facebook, Twitter, etc. Much of this data is user generated or generated by computers. Many companies are trying to figure out how to use this data to target their customers. NoSQL/Big Data is being harvested by server farms using Hadoop, an open source framework to harvest meaning from big data.
For those that are interested, here are some links to videos that explain recent trends in big data.
- Big Data Explained (7:13)
- Big Data (3:30) (Age of Big Data above)
- Big Data Explained (8:33)
- SQL Comparison (6:36)
- What is Hadoop? (3:07) (Hadoop above)
Let's take a look at a relational database that a Library might use.