TimesTen
TimesTen is an in-memory, relational OLTP database management system supporting SQL through Open Database Connectivity (ODBC), Java Database Connectivity (JDBC) and Oracle Call Interface (OCI) APIs. It services very well for real time application because of short response time and high throughput derived from its in-memory characteristics. TimesTen can deployed in following ways: Classic (single node), Cache and Scaleout (distributed, assume this deployment when coming to concurrency-related sections later).
History
TimesTen was originally named as SmallBase and developed by HP Labs. Shortly after its first commercial use in 1995, the product was split out as a separate startup company and renamed as TimesTen. In 2005, the company with 90 employees at the time was acquired by Oracle. TimesTen was then integrated with Oracle software as well as services and become part of Oracle Database Products.
Indexes
B+Tree Hash Table BitMap T-Tree
By default TimesTen uses B+Tree. The original version (SmallBase) from the 1990s supported T-Trees. TimesTen still supports T-Tree indexes but the administrator has to request for the DBMS to use them.
Checkpoints
TimesTen maintains two checkpoint files (ds0 and ds1) on disk to keep track of metadata of in-memory permanent data. It switches two files when a checkpoint is done to ensure there is always at least one completed checkpoint file for backup and recovery purpose. The rate for checkpointing disk writes is configurable by application. It supports fuzzy or non-blocking checkpoints as well as transaction-consistent checkpoints (i.e. blocking checkpoints).
Website
http://www.oracle.com/us/products/database/timesten/index.html
Tech Docs
https://docs.oracle.com/database/timesten-18.1/
Developer
HP Labs
Country of Origin
Start Year
1996
Former Name
SmallBase
Acquired By
Oracle