I have a PostgreSQL 10.6 database which contains a materialized view:
create materialized view field_data.ss_mat AS select s_id, _geometry FROM ss;
PostgreSQL mat view support was added back in 126.96.36.199.
Release 188.8.131.52 correctly opens the Drawing component located within the PostgreSQL data source.
Releases 184.108.40.206 and .9 fail to open that same component with the error "Invalid Data Item".
The Manifold datasource SQL9 DDL are identical; I copied and pasted between the running .0 and .10 applications.
The mat view does not return any "date time" data types (change in Release 220.127.116.11), only the text and geometry fields "s_id" and "_geometry". I don't know if many other folks are using pg mat views, so I thought I'd flag the issue.
Send in a bug report.
Yes, please send in a bug report, like Dimitri says.
Ideally, we'd need example data to reproduce the issue - you could try copy / pasting the table backing the view (ss) into a MAP file then copy / pasting it back to PostgreSQL, creating a similar materialized view on the new table and seeing if it will run into the same issue - if it does, that's great, because we'd be able to reproduce it on our end the same way.