Function execute_columnar 

pub fn execute_columnar(
    rows: &[Row],
    filter: Option<&Expression>,
    aggregates: &[Expression],
    schema: &CombinedSchema,
) -> Option<Result<Vec<Row>, ExecutorError>>

Execute a query using columnar processing (AST-based interface)

This is the entry point for columnar execution that accepts AST expressions and converts them to the columnar execution pipeline.

Arguments

• rows - The rows to process
• filter - Optional WHERE clause expression
• aggregates - SELECT list aggregate expressions
• schema - Schema for resolving column names to indices

Returns

Some(Result) if the query can be optimized using columnar execution, None if the expressions are too complex for columnar optimization.

Note: This function uses LLVM auto-vectorization for vectorized execution.