presto-memory/src/main/java/io/prestosql/plugin/memory/MemoryMetadata.java/MemoryMetadata/beginInsert
class MemoryMetadata:    @Override
    public synchronized MemoryInsertTableHandle beginInsert(ConnectorSession session, ConnectorTableHandle tableHandle)
    {
        MemoryTableHandle memoryTableHandle = (MemoryTableHandle) tableHandle;
        return new MemoryInsertTableHandle(memoryTableHandle.getId(), ImmutableSet.copyOf(tableIds.values()));
    }