SELECT

trader,

'Arbitrum' AS chain,

MIN(block_timestamp) AS min_date

FROM

arbitrum.vertex.ez_perp_trades

GROUP BY

trader

UNION ALL

SELECT

trader,

'Base' AS chain,

MIN(block_timestamp) AS min_date

FROM

base.vertex.ez_perp_trades

GROUP BY

trader

UNION ALL

SELECT

trader,

'Mantle' AS chain,

MIN(block_timestamp) AS min_date

FROM

mantle.vertex.ez_perp_trades

GROUP BY

trader

UNION ALL

SELECT

trader,