Struct TypeMapper 

pub struct TypeMapper;

Type mapper for converting between Exasol and Arrow types.

Implementations

impl TypeMapper

pub fn exasol_to_arrow( exasol_type: &ExasolType, nullable: bool, ) -> Result<DataType, ConversionError>

Convert an Exasol type to an Arrow DataType.

Arguments

• exasol_type - The Exasol type to convert
• nullable - Whether the field is nullable

Returns

The corresponding Arrow DataType

Errors

Returns ConversionError::UnsupportedType if the type cannot be mapped

pub fn arrow_to_exasol( arrow_type: &DataType, ) -> Result<ExasolType, ConversionError>

Convert an Arrow DataType to an Exasol type.

This is used for parameter binding and type inference.

Arguments

• arrow_type - The Arrow type to convert

Returns

The corresponding Exasol type

Errors

Returns ConversionError::UnsupportedType if the type cannot be mapped

pub fn create_field_metadata( exasol_type: &ExasolType, ) -> HashMap<String, String>

Create Arrow field metadata to preserve Exasol type information.

This allows round-tripping type information.

pub fn from_field_metadata( metadata: &HashMap<String, String>, ) -> Option<ExasolType>

Extract Exasol type from Arrow field metadata.