private void addUniqueIndex(Table table, Set<String> oldPks) {
        final Index pkReplacement = table.mutator().addNewIndex();
        final String idxName = md5(oldPks.toString());

        final IndexMutator<? extends Index> mutator = pkReplacement.mutator();
        mutator.setId(idxName);
        mutator.setName(idxName);
        mutator.setUnique(true);

        table.primaryKeyColumns().forEachOrdered(pkc -> {
            final int ordNo = 1 + (int) pkReplacement.indexColumns().count();
            final IndexColumn idxCol = mutator.addNewIndexColumn();
            idxCol.mutator().setId(pkc.getId());
            idxCol.mutator().setName(pkc.getName());
            idxCol.mutator().setOrdinalPosition(ordNo);
        });
    }
'true' below might speed up metadata retrieval since approximations can
be used. See https://github.com/speedment/speedment-enterprise/issues/168
runtime-parent/runtime-connector-parent/sqlite/src/main/java/com/speedment/runtime/connector/sqlite/internal/SqliteMetadataHandlerImpl.java