How do I prevent my dwarf from getting stuck on the wrong side of a wall?

I dig my way to a small pool and flood an area to use as a farm. Now I'm told I want to wall it up before it rains and floods my fortress. I build a wall, but the dude who comes and builds it gets trapped on the wrong side of the wall. What can I do to avoid this?

Solution 1:

Build(b->C->w) a wall on the side you don't want your dwarves trapped on, but suspend the construction before it's built(q->s). Then when the original wall is done, cancel the suspended wall(q->x).

Solution 2:

the other approach is to plan your wall placements according to work orders. Your dwarfs will always want to stand next to the wall in this order: Top, Left, Right, Bottom. So. Build your top left walls first. all the other walls will be built from the inside the way you would hope.