Example:

<verbatim>
  CREATE TABLE t1(b COLLATE nocase);
  INSERT INTO t1 VALUES('abc');
  INSERT INTO t1 VALUES('ABC');
  INSERT INTO t1 VALUES('aBC');

  -- correctly returns: "ABC aBC abc"
  SELECT * FROM t1 ORDER BY b COLLATE binary;

  -- incorrectly omits external sort and returns: "abc ABC aBC"
  SELECT * FROM t1 WHERE b='abc' ORDER BY b COLLATE binary;
</verbatim>