While I am not familiar with the TOP syntax, I bet ROWNUM can be used to do the same. ROWNUM is a the number of a row as it was retrieved from the table (this differs from the display order) -- to limit results to 10 rows, you can use WHERE ROWNUM <= 10. (Please note: this takes place before sorting, so it is no good for getting the "top 10" and such.)

SELECT *
  FROM scott.emp
  WHERE ROWNUM = 1;
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