Used as values in concatenate()'s merge argument:
MERGE_SKIP skips the property (default), MERGE_LAST_VALUE uses the
last source containing it, MERGE_COLLECT_AXIS collects values along
the dataset_axis.
Used as values in concatenate()'s merge argument:
MERGE_SKIP skips the property (default), MERGE_LAST_VALUE uses the
last source containing it, MERGE_COLLECT_AXIS collects values along
the dataset_axis.