`PrimitiveVector` should as a logical data type

[v0y4g3r]

PrimitiveVector contains a primitive array, but the logical data type of vector may differ from it's internal array, for example, DateVector is represented by a Int32Vector, but the logical type is Date.

In fact, arrow's PrimitveArray::new accepts a parameter to specify it's logical data type, so PrimitiveVector should also have a logical data type.

[evenyag]

We may also need to move the serialization of Vector to DataType, so we could serialize the elements based on vector's logical type.

[waynexia]

I suggest changing the parameter Primitive of PrimitiveVector to LogicalType (or another naming). With a type parameter PhysicalType. Just like this in arrow - ArrowPrimitiveType and type parameter Native.

[tisonkun]

pub struct PrimitiveVector<T: LogicalPrimitiveType> {
    array: PrimitiveArray<T::ArrowPrimitive>,
}

This is implemented now? @v0y4g3r @waynexia

[evenyag]

This is related to the arrow2 crate, I guess we can close this issue now.

[tisonkun]

No longer relevant.