"Donald Where's Your Troosers?" was the first record released by Andy Stewart. As might be suspected from the title, it is a novelty song, a variation on that old joke: what does a Scotsman wear under his kilt? Actually, there are several jokes about this, but none that can be repeated here.
According to Desmond Carrington in a February 2013 radio documentary The Music Goes Round..., Stewart wrote the lyric in 10 minutes while sitting in the toilet. Carrington said the moral is you can spend a penny and make a fortune. The music was written by Neil Grant.
Released in 1960, the song reached #37 UK. In 1989, it was re-released, this time climbing to #4.
Running to 3 minutes 17 seconds, this was released originally on the EMI Top Rank label, and the following year on Warwick.
Suggestion credit: Alexander Baron - London, England, for all above