TRACE 输出的示例

以下示例显示了 items_pct 过程中的样本跟踪输出，这些输出出现在 SET DEBUG FILE TO 语句所指定的文件中。这些输出显示过程变量、过程参数、返回值和错误代码的值。

trace expression :begin trace
          trace on
          expression:
          (select (sum total_price)
          from items)
          evaluates to $18280.77 ;
          let  tp = $18280.77
          expression:
          (select (sum total_price)
          from items
          where (= manu_code, mac))
          evaluates to $3008.00 ;
          let  mc_tot = $3008.00
          expression:(/ mc_tot, tp)
          evaluates to 0.16
          let  pct = 0.16
          expression:(> pct, 0.1)
          evaluates to 1
          expression:(- 745)
          evaluates to -745
          raise exception :-745, 0, ''
          exception : looking for handler
          SQL error = -745 ISAM error = 0  error string =  = ''
          exception : no appropriate handler