SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fd535a0c3b41674069f0ecfbeb4e57d77a9ca93171b3b747d61ded308262b7e1' 
  AND token = 'WUYaABMDHaIdUoLYJcf/RYdMc0kl28IMOFl2CWh9YLo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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