Painting of walls and ceiling after patching with drywall compound?

I have patched existing wall and ceilings that were previously painted. Some patches are several square inches. I am going to put two coats of paints on the ceiling and on the wall. Do I need to apply a primer coat to the ceiling and walls. Is spot priming okay or should I prime the complete area.Painting of walls and ceiling after patching with drywall compound?
Since the rest of the walls are already painted you can spot prime the patches.Painting of walls and ceiling after patching with drywall compound?
They're right. But if the existing paint is a gloss you should consider priming the whole thing, or at least paint a test area first, to make sure you have good adhesion.
Sand and prime the areas you patched only Good Luck
If you are applying two coats of paint there's no need to prime the entire area,spot priming is ok.One note, if the new color is the same as the existing color,one coat should be fine
If the walls/ceiling haven't been painted for a while then I would prime the whole area. You can also tint the primer w/some of the finish color which should actually save you having to do the 2 coats you mentioned. I like to prime the whole area because priming seals the surface and helps guarantee a more uniform final finish. It also help highlight imperfections that may have been missed that will need to be corrected before that final coat goes on. This is particularly important if you are using a finish coat that has a sheen to it, e.g., satin, eggshell, semi-gloss finish.