Thank you chacham. The select * is working without any problems. I will paste the headings somewhere below for reference. My problem is that I cannot store the headings "sid = $row->{sid} \tgender = $row->{gender}\n"; into the variable $columns and then use that variable to describe the columns I wish to see in the output

Headings

<code>sid name genotype gender tgroup <\code>

Many thanks for responding