SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9b715a5ba81163943c1378cdb48d8bf100e1960139221173ec222c9ed2efac57' 
  AND token = 'fYb70NKHxudZZdl75Qu1r13qL5w0JOUhdAChIAmQ1os=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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