由于您使用的是rdd，而没有df，并且具有使用简单日期检查的日期字符串，因此以下RDD的简化方法如下:

Since you are working with rdd's and no df's and you have date strings with simple date checking, the following non-complicated way for an RDD:

val rdd = sc.parallelize(Seq((69062,"FRANK","ANALYST",5646, "1991-12-03",3100.00,2001),(63679,"SANDRINE","CLERK",69062,"1990-12-18",900.00,2001)))
rdd.filter(p=>(p._5 < "1991-01-01")).foreach(println)