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SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = 'e8c41531bbbf0042edc725be381cc11e51bc7e31064ff71f171f86f17381b718' 
  AND token = 'O8FsjKKZaKDGQOLNyXFhts1sfFHiqoJfA6tRhB47g2A=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}