How to cast a char[] to varchar?

I have a column defined as "char(3)[]" which I would like to copy into a
different column defined as "varchar(255)".

I've tried to cast the char(3)[] field using "CAST( ... as varchar)" but
I get an error message, "Cannot cast type '_bpchar' to 'varchar'".

Any suggestions?

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Jon Lapham
Extracta Moléculas Naturais, Rio de Janeiro, Brasil
email: lapham(at)extracta(dot)com(dot)br web: http://www.extracta.com.br/
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