text: show collation abc;
  show collation show;
  show collation 1;
  show collation wher charset='iso88591';
  show collation order by 1;
  show collation where charset='iso88591' order by 1 desc;
  show collation where charset='iso88591' order by charset desc;
  show collation 'aa';
  set @a='show';
  show collation @a;
  prepare st from 'show collation 1';
  drop variable @a;
  set names iso88591;
  