Plugin can’t write to database even though permissions appear correct?

The Formidable Form plugin seems to ignore database errors in many places in the code. Setting WP_DEBUG to true uncovered that the forms are not created because some tables are missing (no indication is given to the user).

Further investigation has shown that the tables fail to create when the plugin is activated (no indication is given to the user).

The underlying root cause that leads to table creation failure is that some of the tables are using nullable fields in unique keys, which is currently not supported by the Cloud Storage Engine (ClouSE). So the solution here is to alter the creation statement to make the fields that are used in unique keys not nullable. The patch is provided via OblakSoft support channels.