SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd75faec8470ca903789ace68743474e109c12a194a6b4f65e4585945bf4a1187' 
  AND token = 'Plk4Lf2/TLpsPmPhWId61qlJg6fC+/i5limWDX953lQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}