MariaDB 11.4

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select version();


version()


11.4.4-MariaDB-deb12


CREATE TABLE players (
    playerId INT,uniqueId VARCHAR(20),game VARCHAR(20),
    merge VARCHAR(20)
);

INSERT INTO players (playerId, uniqueId, game, merge)
VALUES (562, '[U:1:18893661]', 'cstrike', NULL);
select playerId, uniqueId, game,
    cast(SUBSTRING(uniqueId, 6, LENGTH(uniqueId) - 5 -1 ) as UNSIGNED) + 76561197960265728 as communityId
from  players
where playerId = 562;


playerId
uniqueId
game
communityId


562
[U:1:18893661]
cstrike
76561197979159389