pub fn extract_column<'a, T: Array + 'static>(
cols: &'a [ArrayRef],
column_key: &'static str,
column_index: usize,
expected_type: DataType,
) -> Result<&'a T, EncodingError>
Expand description
Extracts and downcasts the specified column_key
column from an Arrow array slice.
§Errors
Returns an error if:
column_index
is out of range:EncodingError::MissingColumn
.- The column type does not match
expected_type
:EncodingError::InvalidColumnType
.