all
Checks if all rows in the DataFrame satisfy the predicate.
Returns Boolean — true if every row satisfies the predicate, false otherwise.
all { rowCondition }
rowCondition: (DataRow) -> Boolean
Related operations: any, filter, single, count.
Examples
df
Check if all persons' age is greater than 21:
df.all { age > 21 }
Output:
false
Check if all persons have age greater or equal to 15:
df.all { name.first().isUpperCase() && age >= 15 }
Output:
true
18 September 2025