There are at least four ways to get to StackExchange data: OData (http://data.stackexchange.com/stackoverflow/atom/), Data Explorer (http://data.stackexchange.com/), XML data dumps (https://archive.org/details/stackexchange), and the API (http://api.stackexchange.com/2.2/).
The first three used to have EmailHash as a field in the User object. However, EmailHash is missing from all recent data I can find. This is documented here:
- http://data.stackexchange.com/stackoverflow/query/new shows the database schema, with User objects having EmailHash field. However, any search on this field fails to find any rows (see e.g. http://data.stackexchange.com/stackoverflow/query/153930/find-user-by-email-hash)
- https://ia600603.us.archive.org/34/items/stackexchange/readme.txt shows that the Users.xml file should have EmailHash. However, all the files in the data dump are missing this field.
- http://data.stackexchange.com/stackoverflow/atom/Users has a field for EmailHash, but it is always NULL.
Could someone who knows explain why EmailHash is not currently being provided? Is this an oversight, or a policy change?