SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '896ddb7201d6707dd7d2643a96c2f85006a73df22f544d924d2caa0b9f43b7c8' 
  AND token = 'YhlQOlmY0p5Vco+PKvBwfHashGbkXPcM5+sDMzLjuto=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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