OLTP (Online Transaction Processing)

OLTP describes database workloads dominated by many short, concurrent transactions — inserts, updates, and single-row lookups — typical of the operational database behind an application, as opposed to analytical (OLAP) workloads.

An e-commerce order system, a banking ledger, or the HR schema used throughout SQLMentor's tutorials are all OLTP workloads: lots of small, fast, concurrent reads and writes, each touching relatively few rows. OLTP schemas are usually normalized to keep writes fast and consistent.

OLTP and OLAP have opposite tuning priorities — an index strategy or schema design optimized for one often hurts the other, which is why large systems frequently separate the two (an OLTP database feeding a separate data warehouse).