SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '08907f955738616b587ff72ad864ab8dd011276082cdc68df724348dac6e2209' 
  AND token = '0cAei0ZGdCk4im3BvpNKr0+6x9CBVnMhxLkGiZBqCR8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00049

JSON explain

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