internal static IReadOnlyList <ColumnDecoder> FieldsToDecoders(IReadOnlyList <Field> fields)
{
List <ColumnDecoder> columnDecoders = new List <ColumnDecoder>(fields.Count);
TypeDecoderVisitor typeDecoderVisitor = new TypeDecoderVisitor();
for (int i = 0; i < fields.Count; i++)
{
var field = fields[i];
var decoder = ArrowTypeToDecoder(field.DataType, typeDecoderVisitor);
decoder.SetOrdinal((uint)i);
if (field.IsNullable)
{
//Add null check decoder if the column can be null
decoder = new NullDecoder(decoder);
}
columnDecoders.Add(decoder);
}
return(columnDecoders);
}
internal static IReadOnlyList <ColumnDecoder> SchemaToDecoders(Schema schema)
{
List <ColumnDecoder> columnDecoders = new List <ColumnDecoder>(schema.Fields.Count);
TypeDecoderVisitor typeDecoderVisitor = new TypeDecoderVisitor();
for (int i = 0; i < schema.Fields.Count; i++)
{
var field = schema.GetFieldByIndex(i);
var decoder = ArrowTypeToDecoder(field.DataType, typeDecoderVisitor);
decoder.SetOrdinal((uint)i);
if (field.IsNullable)
{
//Add null check decoder if the column can be null
decoder = new NullDecoder(decoder);
}
columnDecoders.Add(decoder);
}
return(columnDecoders);
}
private static ColumnDecoder ArrowTypeToDecoder(IArrowType arrowType, TypeDecoderVisitor typeDecoderVisitor)
{
arrowType.Accept(typeDecoderVisitor);
return(typeDecoderVisitor.ColumnDecoder);
}
