sorry, now what I can do is like this :
var df5 = spark.read.parquet("/user/devuser/testdata/df1").coalesce(1)
df5 = df5.union(df5).union(df5).union(df5).union(df5)
2018-12-14
lk_spark
发件人：15313776907 <15313776...@163.com>
发送时间：2018-12-14 16:39
主题：Re: how to generate a larg dataset paralleled
收件人："lk_sp...@163.com"<lk_sp...@163.com>
抄送："user@spark.apache.org"<user@spark.apache.org>
I also have this problem, hope to be able to solve here, thank you
On 12/14/2018 10:38，lk_spark<lk_sp...@163.com> wrote：
hi,all:
I want't to generate some test data , which contained about one hundred
million rows .
I create a dataset have ten rows ,and I do df.union operation in 'for'
circulation , but this will case the operation only happen on driver node.
how can I do it on the whole cluster.
2018-12-14
lk_spark
