<databaseChangeLog
  xmlns="http://www.liquibase.org/xml/ns/dbchangelog"
  xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
  xsi:schemaLocation="http://www.liquibase.org/xml/ns/dbchangelog http://www.liquibase.org/xml/ns/dbchangelog/dbchangelog-3.0.xsd">

  <changeSet author="seber" id="add-department-creation-date-column">
    <addColumn tableName="Department" >
      <column name="createdAt" type="date">
        <constraints nullable="false" />
      </column>
    </addColumn>
    <update tableName="Department">
      <column name="createdAt" value="1970-01-01" />
      <where>createdAt IS NULL</where>
    </update>
  </changeSet>
</databaseChangeLog>

<databaseChangeLog
  xmlns="http://www.liquibase.org/xml/ns/dbchangelog"
  xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
  xsi:schemaLocation="http://www.liquibase.org/xml/ns/dbchangelog http://www.liquibase.org/xml/ns/dbchangelog/dbchangelog-3.0.xsd">

  <changeSet author="seber" id="add-department-creation-date-column">

    <validCheckSum>8:39dda6c8a7c57434b6938dfb67c6bf48</validCheckSum>

    <preConditions>
      <tableExists tableName="Department"/>
      <not>
        <columnExists tableName="Department" columnName="createAt"/>
      </not>
    </preConditions>

    <addColumn tableName="Department">
      <column name="createdAt" type="date" defaultValue="1970-01-01">
        <constraints nullable="false"/>
      </column>
    </addColumn>
  </changeSet>
</databaseChangeLog>

Fix mysql not nullable column date creation
Fix mysql not nullable column date creation
