oracle - one-to-many relationshipt with database constrain and inverse=true -

there 2 classes , b , hibernate mappings

<hibernate-mapping  default-lazy="false">         <class name="a" table="a">             <id name="id" type="long">                   <generator class="sequence"><param name="sequence">a_sequence</param></generator></id>      <set name="a" cascade="all" inverse="false"  >             <key><column name="a_fk" not-null="true" /></key>             <one-to-many class="b" /></set>    </class> </hibernate-mapping>  <hibernate-mapping  default-lazy="false">     <class name="b" table="b">         <id name="id" type="long"> <column name="id"/>             <generator class="sequence"><param name="sequence">b_sequence</param></generator></id>        </class> </hibernate-mapping> 

on database there not null contraint , foreign key constraint on column a_fk of table b. when try insert contains b following error:

ora-01400: cannot insert null ("schema"."b"."a_fk")

is possible insert kind of data without having specify inverse=true flag? , inverse relationship?

not without getting rid of way id generated. can switch how id generated?