SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '3b4aeb5c3c104c85b27f3ccec1d0ecbca91933dc16b091af481d24cc9b82f469' 
  AND token = 'gxU3/GDx60UAj2/kwBvy7gNQKVOg9uim7wI4uDXKzC0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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