Appendix - Additional Information relating to Log Propagation

Actian Vector is a columnar relational database that utilizes performance features in modern CPUs to perform extremely fast data analysis and reporting. Although Vector is ACID compliant, transaction secure and supports all DML operations, it is not meant to be used for an OLTP type workload and transaction processing.

Traditionally, incremental updates is a weakness of column based database systems. Vector uses a new innovative technique by keeping track of the tuple position and performing incremental updates in a new, in-memory data structure called Positional Delta Tree (PDT) for maintaining such positional updates.

Updates that reside in memory can potentially consume a significant percentage of system memory. As a result, Vector automatically propagates the changes buffered in memory to disk-resident tables (UpdatePropagation) and provides statements for manually propagating in-memory updates to disk (COMBINE).