I am not sure what the name of this cactus is but I have had it for decades. It was maybe 15 cm (4 inches) tall when I bought it now it is over 210 cm (6 feet). The flower only opens at night and I think it only opens one night. I will take time interval pictures again tonight. Last night, I took these pictures and then thought I had set the camera to take a picture every 15 minutes for 10 hours. Unfortunately, I did not set up the Canon intervalometer correctly. I should have taken the first picture to start the process going but did not.
The pictures shown at this Photo Camel site taken by Matrix Imagery seem to match what I have. If they do match, then my cactus is a Cereus peruvianus or Cereus uruguayanus. It is also has some other names like Night Blooming Cereus or Peruvian Apple according to this Plant-Care website.