SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '69de3446eace920e8ddcc36a51d0bf53d231ec53311f5e834c8491523bc414b9' 
  AND token = 'QEgYlyAKjcHLVUIl1/xUR4wLU6pUz6gooKcyWJGuu7g=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00057

JSON explain

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