SQLQuery nativeQuery = ...;
final Collection<String> spaces = nativeQuery.getSynchronizedQuerySpaces();

// false by default
final boolean autoFlush = isEnabled( "hibernate.auto_flush_before_native_query", false );

if ( autoFlush && spaces.isEmpty() ) {
    flush();
}
else {
    // legacy behavior - just flush explicitly synchronized tables
    autoFlushIfRequired( spaces );
}