This is the below Hive Table
CREATE EXTERNAL TABLE IF NOT EXISTS SampleTable
(
USER_ID string,
DETAIL_DATA array<struct<key:string,value:string>>
)
And this is the data in the above table-
11111 [{"key":"client_status","value":"ACTIVE"},{"key":"name","value":"Jane Doe"}]
Is there any way I can get the below output using HiveQL?
**client_status** | **name**
-------------------+----------------
ACTIVE Jane Doe
I tried use explode() but I get result like that:
SELECT details
FROM sample_table
lateral view explode(DETAIL_DATA) exploded_table as details;
**details**
-------------------------------------------+
{"key":"client_status","value":"ACTIVE"}
------------------------------------------+
{"key":"name","value":"Jane Doe"}
Use laterral view [outer] inline
to get struct elements already etracted and use conditional aggregation to get values corresponting to some keys grouped in single row, use group_by user_id.
Demo:
with sample_table as (--This is your data example
select '11111' USER_ID,
array(named_struct('key','client_status','value','ACTIVE'),named_struct('key','name','value','Jane Doe')) DETAIL_DATA
)
SELECT max(case when e.key='name' then e.value end) as name,
max(case when e.key='client_status' then e.value end) as status
FROM sample_table
lateral view inline(DETAIL_DATA) e as key, value
group by USER_ID
Result:
name status
------------------------
Jane Doe ACTIVE
If you can guarantee the order of structs in array (one with status comes first always), you can address nested elements dirctly
SELECT detail_data[0].value as client_status,
detail_data[1].value as name
from sample_table
One more approach, if you do not know the order in array, but array is of size=2, CASE expressions without explode will give better performance:
SELECT case when DETAIL_DATA[0].key='name' then DETAIL_DATA[0].value else DETAIL_DATA[1].value end as name,
case when DETAIL_DATA[0].key='client_status' then DETAIL_DATA[0].value else DETAIL_DATA[1].value end as status
FROM sample_table