Pfthb

with calls as (

SELECT 
 call_started
 , mobile_id
from calls
)

, ranking as (
select 
 mu.mobile_id
 , mu.version
 , mu.created_at
 , c.call_started
 , rank() over (partition by mu.mobile_id order by mu.created_at desc) as rank 

from mobile_updates mu
join calls c
 on mu.mobile_id = c.mobile_id 
where mu.created_at < c.call_started
) 

select 
 call_started
 ,version
from ranking 
where rank = 1

with calls as (

SELECT 
 call_started
 , mobile_id
from calls
)

, ranking as (
select 
 mu.mobile_id
 , mu.version
 , mu.created_at
 , c.call_started
 , rank() over (partition by mu.mobile_id order by mu.created_at desc) as rank 

from mobile_updates mu
join calls c
 on mu.mobile_id = c.mobile_id 
where mu.created_at < c.call_started
) 

select 
 call_started
 ,version
from ranking 
where rank = 1

with calls as (

SELECT 
 call_started
 , mobile_id
from calls
)

, ranking as (
select 
 mu.mobile_id
 , mu.version
 , mu.created_at
 , c.call_started
 , rank() over (partition by mu.mobile_id order by mu.created_at desc) as rank 

from mobile_updates mu
join calls c
 on mu.mobile_id = c.mobile_id 
where mu.created_at < c.call_started
) 

select 
 call_started
 ,version
from ranking 
where rank = 1

with calls as (

SELECT 
 call_started
 , mobile_id
from calls
)

, ranking as (
select 
 mu.mobile_id
 , mu.version
 , mu.created_at
 , c.call_started
 , rank() over (partition by mu.mobile_id order by mu.created_at desc) as rank 

from mobile_updates mu
join calls c
 on mu.mobile_id = c.mobile_id 
where mu.created_at < c.call_started
) 

select 
 call_started
 ,version
from ranking 
where rank = 1

Your Answer

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