RDBMS [Describe how rdbms differs from other dbms, and list a few examples.]
This is not very scientific, but it's how I like to think of it.
Basically a db is a set of related data, a typical db have lists of values (tables of rows), each value is a list values (table columns), sometime a value (a field) is it self a list of values (a record from another list, hence relational)
Sql (THE standard rdbms language) is used to define the lists, the relations and to insert a retrieve values.
A non-standard procedural language is used to define triggers and procedures, with is compensate for what Sql can't to and add more restrictions (control if you prefer) on the values in the db.
Some of the cool programmers I met on the net, seems to think that rdbms is overrated, I have no clue why? But I intend to invetigate more on when it can be a bad idea to use a rdbms.
Most rdbms(es) promises to be ACID compliant. ACID are or should be the proporties of any db transaction . (A Atomicity, a TXN is performed in its entirety or not at all) (C Consistency, a correct TXN takes the db from one consistant state to another) (I Isolation, until they become committed, updates by a TXN are not visible to other TXN) (D Durability, once committed changes must never be lost)
I personally find that between A and I, C seems redundant. It would be nice if someone can justify what C adds exactly.
Question: what is considered a transaction in a db and whatnot? Is data retrieval (Sql select statements) considered a db TXN.
Sometimes it is said that rdbms is a db topologies, other topologies include (network and hierarchical)
A not new variation of rdbms(es) is ORDBMS(es) or Object-relational db management systems.
Also OO-dbms are talked about, of course after I realized inheritance is just a relation, I started to think that OO-dbms are irrelevant and I started to doubt the intentions/good will of OO-dbms enthusiasts (or sellers).
Also the O in ordbms is nothing to get excited about! Try for yourself.