Columnar Layouts and Vectorized Execution
Columnar storage places values of the same field together, enabling projection, compression, SIMD-friendly scans, and late materialization.
Planned model
Execute the same filter and aggregate over row and column layouts. Count bytes loaded, cache lines, decoded values, branches, and vector lanes.
Questions
- Which workload needs whole records and which needs a few columns?
- How do nulls and variable-length values alter the layout?
- When does compression improve speed by reducing memory traffic?
Exercise
Design a column representation for timestamp, symbol, price, quantity, and optional venue fields.