The most useful thing to know before buying a small dining table is to measure the walking space around it with chairs pulled out, not just the table itself. A table that looks modest in a showroom can turn a kitchen into an obstacle course once four chairs are pushed back at once. Thirty six inches of clearance on at least one side is the number I actually use, because anything less and someone's always squeezing past with a plate.
If you own none of this kind of furniture yet, start with a round or drop leaf table in a mid size, something that seats four comfortably but can flex down to two when it's just you and dinner on a tray. A fixed rectangular table looks sharp in photos but it locks you into one shape of room forever, and most small dining spaces change their mind more than people expect, a desk one year, a card table the next, company on a Sunday.
These tables do their best work in apartments, breakfast nooks, galley kitchens and any house where the dining room and the kitchen are really the same eight feet of floor pretending otherwise. They carry a home through every season without much fuss, though I'll say a lighter wood or a washable top matters more in summer, when doors are open and bare feet track in grass and sand, than it does in winter when everyone's mostly sitting still with soup.
In an ordinary room, a small dining table sits well with mismatched chairs rather than a matching set, it reads less like a showroom and more like a house people actually live in. A simple pendant light overhead earns its spot here more than almost anywhere else in the house, since the table is usually the one surface in the room without a lamp nearby. Keep the rug underneath it flat and tight woven, because anything with a deep pile catches chair legs and drives everyone a little mad by the second week.
What holds up and what doesn't becomes obvious fast. A painted finish shows every water ring within a month. A solid wood top with a simple oil finish takes spills, crayon, hot mugs and a move across town without complaint, and a light sanding every couple of years brings it back like nothing happened.
Before buying, I'd ask myself one thing standing in the shop: if this table had to double as a desk, a homework station and a dinner table for six on Thanksgiving, would it still hold up, or am I buying it for the one dinner party I'll host this year?