WITH tabel1 AS (SELECT BLOCK_NUMBER,BLOCK_TIMESTAMP,
DATEDIFF(SECOND, LAG(BLOCK_TIMESTAMP) OVER (ORDER BY BLOCK_TIMESTAMP), BLOCK_TIMESTAMP ) AS diff
FROM polygon.core.fact_blocks---i us general tabel
WHERE block_timestamp > '2022-01-01'----times
ORDER BY BLOCK_NUMBER )
SELECT
AVG(diff) AS average_time---Average
FROM tabel1