vivo筆試Hive

現有表 vivo 格式如下左圖所示：params 爲 map 類型數據，請將 params 解析爲右圖所示格式：

創建表vivo

create table if not exists vivo(
name string,
params map<string,int>
)
row format delimited
fields terminated by '\t'
collection items terminated by '&'
map keys terminated by ':'
stored as textfile
;

加載數據到vivo表

load data local inpath '/myfile/gqds/vivo.txt' overwrite into table vivo;

查詢

select 
name,
tmp.key course,
tmp.value score
from vivo
lateral view explode(params) tmp
;

結果行轉列

select 
t.name name,
sum(case when t.course='math' then score else 0 end) math,
sum(case when t.course='english' then score else 0 end) english
from (
select
name,
tmp.key course,
tmp.value score
from vivo
lateral view explode(params) tmp
) t
group by name
;