SQL would then do the summing against the internal table, displaying this report. The SUM(ORDER$) results, though they look
fine at first glance, are actually incorrect. That's because ORDER$ has been duplicated for each Order Detail record, causing it to be overstated when the summing is performed.
According to Software AG, only a user with a good grasp of SQL theory would have known that summing at two levels of detail in the same SELECT statement would produce erroneous results. Unlike most query tools, Esperant's SQL Expert would have grayed out the QTY column the instant you chose to SUM the ORDER$ column. The query would produce the following SQL code along with the correct report table:
Flexible C++
Matthew Wilson
My approach to software engineering is far more pragmatic than it
is
theoretical--and no language better exemplifies this than C++.
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