Gets the unique elements from the input dataset.

The input dataset must yield batched rank-1 tensors. This function reads each coordinate of the tensor as an individual element and return unique elements.

dataset A Element type must be tf.string.
string_max_bytes The maximum length (in bytes) of strings in the dataset. Strings longer than string_max_bytes will be truncated. Defaults to None, which means there is no limit of the string length.

A rank-1 Tensor containing the unique elements of the input dataset.

ValueError -- If the shape of elements in dataset is not rank 1. -- If string_max_bytes is not None and is less than 1.
TypeError If dataset.element_spec.dtype must be tf.string is not tf.string.