migrations.xml

<?xml version="1.0" encoding="UTF-8"?>
<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-3.1.xsd">

   <changeSet id="2" author="sc">
    <preConditions onFail="CONTINUE">
            <sqlCheck expectedResult="0">
              select count(*) from user_sequences where sequence_name = 'SEQUENCE_NAME_SEQ';
            </sqlCheck>
    </preConditions>
    <createSequence sequenceName="SEQUENCE_NAME_SEQ"/>
   </changeSet>

    <changeSet id="1" author="dmj">
        <createTable tableName="Policy">
            <column name="id" type="varchar(255)">
                <constraints nullable="false"/>
            </column>
            <column name="tenant" type="varchar(255)">
                <constraints nullable="false"/>
            </column>
            <column name="subject" type="varchar(255)">
                <constraints nullable="false"/>                
            </column>
            <column name="policy" type="MEDIUMTEXT"/>
        </createTable>
        <addPrimaryKey columnNames="tenant, id" tableName="Policy"/>
    </changeSet>
    <changeSet id="2" author="dmj">
        <createIndex
                indexName="idx_policy_by_tenant_subject"
                tableName="Policy"
                unique="false">
            <column name="tenant" type="varchar(255)"/>
            <column name="subject" type="varchar(255)"/>
        </createIndex>
    </changeSet>
</databaseChangeLog>