We are hitting some limitations with the field types being generated by bolt. Is there a specific reason you feel the need to use longtext? These fields have a theoretical size of 4GB, this is a waste of memory.
We are getting the following errors when our contenttypes have many fields with longtext. These are html, image etc fields in the yaml converted to mysql "longtext" fields when "text" should be sufficient.
SQLSTATE: Syntax error or access violation
: 1118 Row size too large (> 8126). Changing some columns to TEXT or BLOB or using ROW_FORMAT=DYNAMIC
or ROW_FORMAT=COMPRESSED may help.