presto-spi/src/main/java/io/prestosql/spi/connector/classloader/ClassLoaderSafeConnectorMetadata.java/ClassLoaderSafeConnectorMetadata/dropColumn
class ClassLoaderSafeConnectorMetadata:    @Override
    public void dropColumn(ConnectorSession session, ConnectorTableHandle tableHandle, ColumnHandle column)
    {
        try (ThreadContextClassLoader ignored = new ThreadContextClassLoader(classLoader)) {
            delegate.dropColumn(session, tableHandle, column);
        }
    }