SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b959c90ee6a1e107e08ba5ddaa2ef505b8ce0c1e050f03aefc65577393239d9e' 
  AND token = 'cYuryeDR5oY3l1mqNLY2JdVbFnPwTmpkbhJ4J5dbm/M=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}