SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'dcdd3d6887610a168dc13c406436009a524c2353866846eaca111c1d20976b39' 
  AND token = 'FoZYaGcSPbtfH+QqXYGair32vAb9ohm/1O3NQhwYVpM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00081

JSON explain

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