SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bf82cf0306075865cb448dd00081b17cb61283977224235a4bbf40c784a6cd69' 
  AND token = 'gE7z6/bWj5OtTOGrna5LgBCUzVfB49ioyoUxMTkzbRo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00014

JSON explain

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