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crookm/work_dist_query.sql

Created February 7, 2018 04:52
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Atomic selection of work that prevents race conditions
Raw
work_dist_query.sql
UPDATE work
SET
`worker_id` = ?,
`worker_claimedAt` = NOW()
WHERE
(`worker_id` IS NULL
OR `worker_claimedAt` < DATE_SUB(NOW(), INTERVAL 30 SECOND))
AND `active` = 1
ORDER BY `worker_lastWork` DESC
LIMIT 1;
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