pub fn fix_placeholder_types(plan: &mut LogicalPlan) -> Result<()>Expand description
Give placeholder that cast to certain type data_type the same data type as is cast to
because it seems datafusion will not give data type to placeholder if it need to be cast to certain type, still unknown if this is a feature or a bug. And if a placeholder expr have no data type, datafusion will fail to extract it using LogicalPlan::get_parameter_types