False/True Column constant - scala

Question

TL;DR: I need this spark constant :
val False : Column = lit(1) === lit(0)
Any idea how to do it prettier ?
Problem Context
I want to filter a dataframe from a collection. For exemple
case class Condition(column: String, value: String)
val conditions = Seq(
Condition("name", "bob"),
Condition("age", 18)
)
val personsDF = Seq(
("bob", 30),
("anna", 20),
("jack", 18)
).toDF("name", "age")
When applying my collection to personsDF I expect:
val expected = Seq(
("bob", 30),
("jack", 18)
)
To do so, I am creating a filter from the collection and apply it to the dataframe:
val conditionsFilter = conditions.foldLeft(initialValue) {
case (cumulatedFilter, Condition(column, value)) =>
cumulatedFilter || col(column) === value
}
personsDF.filter(conditionsFilter)
Pretty sweet, right ?
But to do so, I need the neutral value of OR operator which is False. Since False doesn't exist is Spark I used:
val False : Column = lit(1) === lit(0)
Any idea how to do this without tricks ?

Answer 1

You can just do :
val False : Column = lit(false)
This should be your initialValue, right? You can avoid that by using head and tail:
val buildCondition = (c:Condition) => col(c.column)===c.value
val initialValue = buildCondition(conditions.head)
val conditionsFilter = conditions.tail.foldLeft(initialValue)(
(cumulatedFilter, condition) =>
cumulatedFilter || buildCondition(condition)
)
Even shorter, you could use reduce:
val buildCondition = (c:Condition) => col(c.column)===c.value
val conditionsFilter = conditions.map(buildCondition).reduce(_ or _)