将 csv文件导入表格,产生更多具有空值的记录。
create table result(SecondaryRatings String, CommentIds String, LastModeratedTime String)
row format delimited fields terminated by ','
LINES TERMINATED BY '\n'
stored as textfile;
将10条记录导入结果表后,在表中获取12条记录。获取10条记录加上2条额外的空值记录。