I cannot tell what your fnrownum column is supposed to mean. I can guess that its meaning may be well met by counting rows in your table with some ordering criterion (that you have not mentioned.) I hesitate to suggest a real solution because the problem is too ill-defined. However, this would at least produce the result you say you want with the table content you have shown: <code> UPDATE tnTEST set fnrownum = fnidx - 9; </code>