Attribute column order in Data view is not lexicographical
See the sample_set tab here: https://portal.firecloud.org/#workspaces/broad-firecloud-gdac/dev/data
Or simply looking at the filter modal:
There does not appear to be a consistent ordering to the columns. If I were to hazard a guess, it would be the order that the attributes were added to the data model.
As more and more analyses are run on sets of data, the number of attributes on the data model is bound to keep increasing - it would be really nice if the columns could be ordered lexicographically by title to simplify browsing.