Loads all entities contained in the passed-in $results.
.
If the entity belongs to the base table, then it gets stored in
$result->_entity. Otherwise, it gets stored in
$result->_relationship_entities[$relationship_id];
Sql::query in drupal/core/modules/views/lib/Drupal/views/Plugin/views/query/Sql.php
Generate a query and a countquery from all of the information supplied
to the object.
Tables::addField in drupal/core/modules/field_sql_storage/lib/Drupal/field_sql_storage/Entity/Tables.php