Views

Virtual Views

Compression

Dictionary Encoding Delta Encoding Run-Length Encoding Naïve (Page-Level) Bit Packing / Mostly Encoding

Vector compresses each column on a per-page basis for better compression performance. Thus different pages of the same column may be compressed using different algorithms. For the page-level naïve compression, Vector uses LZ4 to compress string values.

Isolation Levels

Snapshot Isolation

Checkpoints

Consistent Blocking

Vector uses blocking consistent checkpoints. The system waits for all running transactions to finish before taking a new checkpoint. Any new transaction is blocked until the checkpoint is completed.

Storage Model

Decomposition Storage Model (Columnar) N-ary Storage Model (Row/Record) Hybrid

Because Vector targets analytical workload, Vector stores tables in columnar model by default. However, if there exists an index where the key spans multiple attributes, these columns are grouped together and stored in the same block. User can instruct Vector to store data in n-ary model.

Concurrency Control

Multi-version Concurrency Control (MVCC) Optimistic Concurrency Control (OCC)

Foreign Keys

Supported

Data Model

Relational

Joins

Hash Join Sort-Merge Join