SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'b2841432281ee67fae65702b505b4354ee6f80f93fca22ded468915cbca1673d' 
  AND token = 'ffcSl46HC3kpJIzHIDIwfKUltxzPNyP4IBiI8ckTNnU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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