what about this

Signed-off-by: Adam Gutglick <adam@spiraldb.com>

Author: AdamGS

encodings/runend/public-api.lock

@@ -88,8 +88,6 @@ pub fn vortex_runend::RunEnd::nbuffers(_array: &vortex_runend::RunEndArray) -> u
 
 pub fn vortex_runend::RunEnd::nchildren(_array: &vortex_runend::RunEndArray) -> usize
 
-pub fn vortex_runend::RunEnd::preferred_arrow_data_type(array: &vortex_runend::RunEndArray) -> core::option::Option<arrow_schema::datatype::DataType>
-
 pub fn vortex_runend::RunEnd::reduce_parent(array: &Self::Array, parent: &vortex_array::array::ArrayRef, child_idx: usize) -> vortex_error::VortexResult<core::option::Option<vortex_array::array::ArrayRef>>
 
 pub fn vortex_runend::RunEnd::serialize(metadata: Self::Metadata) -> vortex_error::VortexResult<core::option::Option<alloc::vec::Vec<u8>>>

encodings/runend/src/array.rs

@@ -11,7 +11,6 @@ use arrow_array::cast::AsArray;
 use arrow_array::types::*;
 use arrow_buffer::ArrowNativeType;
 use arrow_schema::DataType;
-use arrow_schema::Field;
 use vortex_array::ArrayEq;
 use vortex_array::ArrayHash;
 use vortex_array::ArrayRef;
@@ -212,16 +211,6 @@ impl VTable for RunEnd {
         PARENT_KERNELS.execute(array, parent, child_idx, ctx)
     }
 
-    fn preferred_arrow_data_type(array: &RunEndArray) -> Option<DataType> {
-        let ends_dt = array.ends().dtype().to_arrow_dtype().ok()?;
-        let values_dt = array.values().dtype().to_arrow_dtype().ok()?;
-        let values_nullable = array.values().dtype().is_nullable();
-        Some(DataType::RunEndEncoded(
-            Arc::new(Field::new("run_ends", ends_dt, false)),
-            Arc::new(Field::new("values", values_dt, values_nullable)),
-        ))
-    }
-
     fn to_arrow_array(
         array: &RunEndArray,
         data_type: &DataType,

vortex-array/public-api.lock

@@ -1734,7 +1734,7 @@ pub fn vortex_array::arrays::dict::Dict::nbuffers(_array: &vortex_array::arrays:
 
 pub fn vortex_array::arrays::dict::Dict::nchildren(_array: &vortex_array::arrays::dict::DictArray) -> usize
 
-pub fn vortex_array::arrays::dict::Dict::preferred_arrow_data_type(array: &vortex_array::arrays::dict::DictArray) -> core::option::Option<arrow_schema::datatype::DataType>
+pub fn vortex_array::arrays::dict::Dict::preferred_arrow_data_type(_array: &Self::Array) -> core::option::Option<arrow_schema::datatype::DataType>
 
 pub fn vortex_array::arrays::dict::Dict::reduce(array: &Self::Array) -> vortex_error::VortexResult<core::option::Option<vortex_array::ArrayRef>>
 
@@ -1842,7 +1842,7 @@ pub fn vortex_array::arrays::dict::Dict::nbuffers(_array: &vortex_array::arrays:
 
 pub fn vortex_array::arrays::dict::Dict::nchildren(_array: &vortex_array::arrays::dict::DictArray) -> usize
 
-pub fn vortex_array::arrays::dict::Dict::preferred_arrow_data_type(array: &vortex_array::arrays::dict::DictArray) -> core::option::Option<arrow_schema::datatype::DataType>
+pub fn vortex_array::arrays::dict::Dict::preferred_arrow_data_type(_array: &Self::Array) -> core::option::Option<arrow_schema::datatype::DataType>
 
 pub fn vortex_array::arrays::dict::Dict::reduce(array: &Self::Array) -> vortex_error::VortexResult<core::option::Option<vortex_array::ArrayRef>>
 
@@ -5788,7 +5788,7 @@ pub fn vortex_array::arrays::dict::Dict::nbuffers(_array: &vortex_array::arrays:
 
 pub fn vortex_array::arrays::dict::Dict::nchildren(_array: &vortex_array::arrays::dict::DictArray) -> usize
 
-pub fn vortex_array::arrays::dict::Dict::preferred_arrow_data_type(array: &vortex_array::arrays::dict::DictArray) -> core::option::Option<arrow_schema::datatype::DataType>
+pub fn vortex_array::arrays::dict::Dict::preferred_arrow_data_type(_array: &Self::Array) -> core::option::Option<arrow_schema::datatype::DataType>
 
 pub fn vortex_array::arrays::dict::Dict::reduce(array: &Self::Array) -> vortex_error::VortexResult<core::option::Option<vortex_array::ArrayRef>>
 
@@ -21750,7 +21750,7 @@ pub fn vortex_array::arrays::dict::Dict::nbuffers(_array: &vortex_array::arrays:
 
 pub fn vortex_array::arrays::dict::Dict::nchildren(_array: &vortex_array::arrays::dict::DictArray) -> usize
 
-pub fn vortex_array::arrays::dict::Dict::preferred_arrow_data_type(array: &vortex_array::arrays::dict::DictArray) -> core::option::Option<arrow_schema::datatype::DataType>
+pub fn vortex_array::arrays::dict::Dict::preferred_arrow_data_type(_array: &Self::Array) -> core::option::Option<arrow_schema::datatype::DataType>
 
 pub fn vortex_array::arrays::dict::Dict::reduce(array: &Self::Array) -> vortex_error::VortexResult<core::option::Option<vortex_array::ArrayRef>>
 

vortex-array/src/arrays/dict/vtable/mod.rs

@@ -28,7 +28,6 @@ use crate::arrays::ConstantArray;
 use crate::arrays::dict::compute::rules::PARENT_RULES;
 use crate::arrow::ArrowArrayExecutor;
 use crate::arrow::executor::dictionary::make_dict_array;
-use crate::arrow::executor::preferred_arrow_type;
 use crate::buffer::BufferHandle;
 use crate::dtype::DType;
 use crate::dtype::Nullability;
@@ -196,17 +195,6 @@ impl VTable for Dict {
         Ok(())
     }
 
-    fn preferred_arrow_data_type(array: &DictArray) -> Option<DataType> {
-        let codes_dt = array.codes().dtype().to_arrow_dtype().ok()?;
-        let values_dt = preferred_arrow_type(array.values())
-            .or_else(|_| array.values().dtype().to_arrow_dtype())
-            .ok()?;
-        Some(DataType::Dictionary(
-            Box::new(codes_dt),
-            Box::new(values_dt),
-        ))
-    }
-
     fn to_arrow_array(
         array: &DictArray,
         data_type: &DataType,