I think the current confusion is due to the fact that relational databases are too often thought of as data stores. It is true that these DBs are not always the best solution. Sometimes it is better to store data in various NoSQL databases. Sometimes it is even better to store data in a flat file.
However, relational databases provide unprecedented ability to query information. Imagine one person puts data into a black box. 100 other people can ask it questions which were never intended by the original designer, and the system is able to answer those questions fairly efficiently.
The language used to query is orders of magnitude simpler than 'normal' programming languages.
If you query your database and the answer takes too long, you can add an index and the exact same query will start running more quickly!
Two different people can create two different tables. A third person can come in and 'join' these two tables.
I see nosql being a low level technology, higher than blocks/files/b-trees but lower than relational databases. Another way to say it is that relational algebra is the theoretical model while large parts of modern nosql tools are implementation details.
However, relational databases provide unprecedented ability to query information. Imagine one person puts data into a black box. 100 other people can ask it questions which were never intended by the original designer, and the system is able to answer those questions fairly efficiently.
The language used to query is orders of magnitude simpler than 'normal' programming languages.
If you query your database and the answer takes too long, you can add an index and the exact same query will start running more quickly!
Two different people can create two different tables. A third person can come in and 'join' these two tables.
I see nosql being a low level technology, higher than blocks/files/b-trees but lower than relational databases. Another way to say it is that relational algebra is the theoretical model while large parts of modern nosql tools are implementation details.