@Override
    protected ModelInstaller createModelInstaller() {
        return new PostgreSQLTableInstaller(jdbcClient, getManager());
    }
PostgreSQL storage enhanced and came from MySQLStorageProvider to support PostgreSQL.
oap-server/server-storage-plugin/storage-jdbc-hikaricp-plugin/src/main/java/org/apache/skywalking/oap/server/storage/plugin/jdbc/postgresql/PostgreSQLStorageProvider.java