select

trunc(a.block_timestamp,'d') as date,

avg(datediff(second,a.block_timestamp, b.block_timestamp)) as avg_time

from kaia.core.fact_blocks a, kaia.core.fact_blocks b

where a.BLOCK_NUMBER = b.BLOCK_NUMBER-1

group by 1

select

avg(avg_time) as avg_block_time

from block