All I know is that it’s a “database management system”, and I don’t even know what that means! I have tried fooling around with Access and have gotten nowhere. Where do I start and what is the purpose of this?
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A database is just a collection of tables linked by some commonality. If you only have one table, you have a spreadsheet, if you have many tables linked together (we call that a ‘schema’) to produce a *record,* you have a database.
Think of a doctor’s office, it stores patient *records*, those records contain drug information, your history, scans/images, communications, payment methods, etc. It would be a very ugly table to store payment information and scans in the same table as your imaging data. To avoid this you create many tables and generate a schema, or a system that tells the database what columns and rows go together to form a record. This determines your query plan and optimization. You put data in, you have to know how to get it out. Say a table is updated somewhere, does it cascade, does it trigger some other event? Say you are working for that same medical office and you want an email sent out to the patient when their daily medication will run out. You store the information that the patient was given a 90 day count of some medicine, then the database will query itself to find patient records where it is 80 days past the prescription date and it triggers an action, it sends you an email. We call that a ‘stored procedure.’
Access is capable of some level of that, although you would use something like PostGres or Microsoft SQL or Oracle instead of access; but they are fundamentally similar in that they are all RDMS (relational database management systems). Interestingly, while we do talk about ‘relations’ in databases, particularly when we talk about ‘normalization’, but that is not what the ‘relational’ in RDMS is all about. It is a specific kind of algebra pioneered by a genius named Edgar F. Codd. If you fancy the fact you can get data out of a system reliably; in Codd we trust.
[https://en.wikipedia.org/wiki/Relational_algebra](https://en.wikipedia.org/wiki/Relational_algebra)
There is a lot more to this, there are concepts like “ACID”, there are different kinds of databases that don’t use tables at all and use a key/value pair instead. There are graph databases that can relate information by using algorithms. It is a deep topic.
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