ODATA query is empty

I've added a Publish OData Service to my project and pointed it to an entity.

I've given administrator access to the entity with full read / write and also given the Publish OData Service administrator access.

I'm using postman to query the ODATA, and have put MxAdmin username / password combo into the authentication part.

But the query is empty.

For example the URL

http://localhost:8080/odata/ODATA_OS_Transaction/OS_Transaction

returns

<?xml version="1.0" encoding="UTF-8"?>
<feed xml:base="http://localhost:8080/odata/ODATA_OS_Transaction/" xmlns:m="http://schemas.microsoft.com/ado/2007/08/dataservices/metadata" xmlns:d="http://schemas.microsoft.com/ado/2007/08/dataservices" xmlns="http://www.w3.org/2005/Atom">
    <id>http://localhost:8080/odata/ODATA_OS_Transaction/OS_Transaction</id>
    <title>OS_Transaction</title>
    <updated>2017-01-06T12:49:58.967Z</updated>
    <link href="OS_Transaction" rel="self" title="OS_Transaction"></link>
</feed>

and I know that there is data in this table.

Is there anything obvious that I'm doing wrong?