Force a single value base field to be in a separate table? I have a custom entity type (eg: myentitytype), and I would like to add a new base field to it via hook_entity_base_field_info(). As I understand it, single value fields (with a cardinality of 1) will create new columns in the myentitytype_field_data table, but multi-value fields will create a new table.
My question: is it possible to force a single-value field to be stored in its own database table, rather than adding columns to the myentity_field_data table?
Seems the following class is responsible for determining a separate field storage table:
\Drupal\Core\Entity\Sql\DefaultTableMapping::allowsSharedTableStorage

It returns a boolean based on the following 4 conditions:
public function allowsSharedTableStorage(FieldStorageDefinitionInterface $storage_definition) {
  return !$storage_definition-&gt;hasCustomStorage() &amp;&amp; $storage_definition-&gt;isBaseField() &amp;&amp; !$storage_definition-&gt;isMultiple() &amp;&amp; !$storage_definition-&gt;isDeleted();
}

The only feasible solution would be to implement your own Storage handler and flag the basefield with &quot;custom_storage&quot; =&gt; TRUE