check is empty effieciently

[SNEHASISH DUTTA]

Hi,
which is more efficient?

this is already defined since 2.4.0


*def isEmpty: Boolean = withAction("isEmpty",
limit(1).groupBy().count().queryExecution) { plan =>
plan.executeCollect().head.getLong(0) == 0}*

or

* df.head(1).isEmpty*


I am checking if a DF is empty and it is taking forever

Regards,
Snehasish