Function analyze_projection_output_schema 

pub fn analyze_projection_output_schema(
    routines: &dyn RoutineResolution,
    projections: &[ProjectionPlan],
    expression_schema: &RowSchema,
    star_schema: &RowSchema,
    subqueries: &[QueryPlan],
    params: &[SQLParam],
    ctes: &BindingContext<'_>,
) -> Result<RowSchema, SQLError>

Derive and validate a projection’s exact output row type without executing it.