merge multiple tables in Hive SQL - sql

Question

I have two original tables: product table and component tables
Firstly, I need to do an inner merge between these two tables, then create a new table called T1:
select a.Product, a.Plant, b.component, b.position, b.valid_date from Product a
inner join component b on a.Product=b.Product
where a.Plant='A'
The result T1 looks like in the following way:
Furthermore, I need to create a new table named T2 based on T1
select T1.Product, T1.Plant,T1.position,max(T1.valid_date) as valid_date from T1
Where T1.Plant='A'
Group by T1.Product, T1.Plant,T1.position
The result T2 is:
Finally, I want to merge T1 and T2 based on Product, Plant, position, and valid_date for a final table:
select T2.Product, T2.Plant,T1.Component, T2.position, T2.valid_date from T1
INNER JOIN T2 on T1.Product=T2.Product and T1.Plant=T2.Plant and T1.position=T2.position and T1.valid_date=T2.valid_date
where T1.Plant='A'
The final table:
I know this whole process can be done in one hive SQL script. I am confused with multiple tables in one query. I appreciate someone can help me for that. Thank you

Answer 1

isn't it that you just want to do this?
select
a.Plant,b.Product,b.position,b.component,
max(valid_date) as valid_date
from Product a
inner join component b on a.Product = b.Product
where a.Plant = 'A'
group by a.Plant,b.Product,b.position,b.component
db<>fiddle here
the query above produces what you show in output , but based on your comment , I think this is what you are looking for :
select t.Plant,t.Product,t.position,t.component, max(t.valid_date) valid_date
(
select
b.Product, a.Plant,b.component,b.position,max(valid_date) over (partition by a.Plant,b.Product,b.position) as valid_date
from Product a
join component b on a.Product = b.Product
where a.Plant = 'A'
) t
group by t.Plant,t.Product,t.position,t.component;