SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'cd855827e8f972139976fac6a6fcaa3d7559937406fc0a27c0af162b36d6ef90' 
  AND token = 'zCWpZ3jI4SYit6tmCU5ly7EpaipwmNq/oBPv84ALRXs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00050

JSON explain

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