sql">#</a>
</h4>
<p>Operator Fusion Codegen improves the execution performance of a query by fusing an operator DAG into a single optimized
operator that eliminates virtual function calls, leverages CPU registers for intermediate data and reduces the
instruction cache miss. As a general technical optimization, we verified its effectiveness through TPC-DS, and
only some batch operators (Calc, HashAgg, and HashJoin) completed fusion codegen support in version 1.18, getting
significant performance gains on som