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Some key concepts

OLTP

This stands for On Line Transaction Processing, it’s a very old term for an application that serves a lot of customers. A typical commerce or support app would be an OLTP app.

Relational database

If your database is modelled using Codd’s relational algebra it is a relational database. It’s made of relations between tables, that’s it.

RDBMS

This is software that supports the creation and management of relational databases, Relational Database Management System. So things like parsing SQL and turing it into result sets, plus the automation of updating and deleting data are done transparently without you having to do more than send it the SQL to do what you ask.

ACID Transactions

Wikipedia.

  • Atomicity: Each transaction is treated as a single unit that either succeeds or fails.
  • Consistency: The result of any series of transactions goes from one consistent state to another, with each following any validation rules.
  • Isolation: Each transaction takes place in its own space and transactions do not interfere with each other. They will wait until the previous one is complete.
  • Durability: Once data is committed it will remain committed, even in the event of system failure.

Transactions

This is an operation that creates or

DDL

Object-Relational Mapping