As lefty has noted, if you intend to have this "table" installed inside, you DO NOT want to use hydraulics. Hydraulics are overkill for one, as noted, plus if you have an oil leak occur, you are in for a potentially hot, sticky, ugly mess (some hydraulic fluids are corrosive, to boot!). Then there's the expense and learning how to hook up such a system; not easy at all.
Pneumatics (which might be what you are thinking - so many people call pneumatic cylinders "hydraulics" for some reason - must be the lowrider culture or some other confusion?) - are easier to interface with (12-24V air solenoids, usually), but they have their own difficulties, and once again, if you are buying the stuff new, be prepared to spend a hefty sum. They too require pumps, regulators, hoses, manifolds, cylinders, solenoid valving, fittings, pressure vessels, etc.
You don't say what this table is going to do - this will effect what you use (you also don't say how large the table is or what material it is made from - for instance, if you were make a giant's table from steel, for some huge Burning Man-esque surreal sculpture, hydraulics would be what you would need - but I don't think that is the case here).
You might be able to get away with homebrewed pneumatic cylinders, depending on the purpose and the amount of force you need to use; look into homemade motion platforms (home aircraft flight simulation), as well as into homemade pneumatic systems for "dark rides" and "halloween haunted house props"; both of these subjects have followings on the internet, and a lot of information is out there for such projects.
You can homebrew cylinders out of dowelling and PVC pipe; small actuators can be made with syringes and aquarium tubing.
Use an old or cheap airbrush paint air pump for the air source; you could also use a tank of CO2 (with proper ventilation!) and a regulator to reduce the pressure. You could also repurpose an old breathing treatment air pump (nebulizer) - I see these for sale all the time at thrift stores (whatever you do, clean it well!).
Cheap air valving could be made from smaller automatic sprinkler valves, or from solenoid valves for propane use in RVs and boats.
Air lines (depending on pressure needs) could be anything from aquarium tubing to air hoses for shop compressors.