Before going out and purchasing any sort of decorative table lamp, you need to focus your attention on the table which the lamp will sit on. If you're dealing with side tables, it's generally a good idea to ensure that your decorative table lamp doesn't exceed 3 feet in height. Remember, we don't want the lamp to overpower the room.
If you're dealing with a bit of a bigger table, it's still a good idea to stay below 4 feet. Again, don't exaggerate and purchase a monstrosity - it'll easily distract visitors from an otherwise functional room. If you're in the market for a kitchen table lamp, you have a bit more flexibility in choosing your lamp's height. It's generally recommended that kitchen lamps exceed 2 feet in height.
If some sort of disability makes these guidelines seem inconvenient, it might be wise to purchase a floor lamp. While you could exceed these height specifications, you may end up jeopardizing the look of your room. It is best to weigh your options and do what feels best.