Google BQ BI Engine

? What Is BI Engine?

BI Engine is an in-memory vectorized execution engine built on top of BigQuery.

It is NOT just more slots.

? Normal BigQuery Query

Storage → Slots → Shuffle → Aggregate → Return

? With BI Engine

Hot data is cached in memory.

Query path becomes:

Memory → Vectorized execution → Return

Much faster.

? Differences

? When BI Engine Helps

• Repeated dashboard queries

• Aggregated tables

• Small-to-medium datasets

• Sub-second latency requirements

? When It Doesn't

• Massive JOINs

• 10TB aggregations

• Heavy shuffle

BI Engine accelerates scan + compute — but doesn't fix skew.