SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9d72420aa01e15a01c0f4c9a680793c7478324bca020215827bcfbea5624533a' 
  AND token = 'nNu8RBiLaaIlOC9OP3M/9i88Fdpra2W31reF3EhGwBc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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