select wr_id, wr_subject from g4_write_notic where wr_is_comment = 0 and wr_num = '-20' and wr_reply < '' and ((INSTR(wr_20, '정규직')) ) order by wr_num desc, wr_reply desc limit 1

1054 : Unknown column 'wr_20' in 'where clause'

error file : /bbs/board.php