SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '69c1aad24958be64767bca318005ade7cf909aa411617eaced39f606ef72dba7' 
  AND token = 'E+J58fRtADg7TKrG4kEM3StojuZ/g47d3z1CELAHFkQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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