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4. Vectorwise: Beyond Column Stores

Key ideas

Maintains a single copy of all data
I/O - NSM/PAX vs DSM/PAX
Disk storage - compressed data with high decompression rates
DDL allows users to declare one index per table in order to determine the physical tuple order
Maintains (automatically) MinMax indices on all columns to store simple metadata for a given range of values. This is particularly advantageous if there are correlations between attribute values and tuple position
To assist with concurrent scan intensive queries, table scans accept data out-of-order, and a buffer manager determines tuple order at runtime.
Update mechanism is differential in nature and uses a three layer PDT design - a small PDT private to the transaction, a shared CPU-cache resident PDT, and a potentially large RAM-resident PDT to provide snapshot isolation.
Query processing exploits SIMD execution alongwith environment specific optimization
Future - query execution on compressed data, JIT compilation