Hybrid Transactional/Analytical Processing: A Survey Fatma Özcan Yuanyuan Tian Pınar Tözün IBM Resarch - Almaden IBM Research - Almaden IBM Research - Almaden
[email protected] [email protected] [email protected] ABSTRACT To understand HTAP, we first need to look into OLTP The popularity of large-scale real-time analytics applications and OLAP systems and how they progressed over the years. (real-time inventory/pricing, recommendations from mobile Relational databases have been used for both transaction apps, fraud detection, risk analysis, IoT, etc.) keeps ris- processing as well as analytics. However, OLTP and OLAP ing. These applications require distributed data manage- systems have very different characteristics. OLTP systems ment systems that can handle fast concurrent transactions are identified by their individual record insert/delete/up- (OLTP) and analytics on the recent data. Some of them date statements, as well as point queries that benefit from even need running analytical queries (OLAP) as part of indexes. One cannot think about OLTP systems without transactions. Efficient processing of individual transactional indexing support. OLAP systems, on the other hand, are and analytical requests, however, leads to different optimiza- updated in batches and usually require scans of the tables. tions and architectural decisions while building a data man- Batch insertion into OLAP systems are an artifact of ETL agement system. (extract transform load) systems that consolidate and trans- For the kind of data processing that requires both ana- form transactional data from OLTP systems into an OLAP lytics and transactions, Gartner recently coined the term environment for analysis. Hybrid Transactional/Analytical Processing (HTAP).