select

block_hash, block_number, block_timestamp,

trunc(block_timestamp, 'Day') as date,

timestampdiff('Seconds', lag(block_timestamp) over (order by block_number), block_timestamp) as difference

from polygon.core.fact_transactions

group by 1, 2, 3, 4

order by 4, 3)

select date, avg(difference) as Avg_blocktime_diff from a

where date<= '2022-07-24' group by 1 order by 1