Microsoft Office Tutorials and References
In Depth Information
Understanding And and Or
When setting up ﬁ filters, you can make two kinds of comparisons: And and Or. If all we had
were one or the other, there would be no problem, but we have both, and we don’t have
parentheses to help clarify the comparisons.
It helps to understand that And and Or apply to each pair of rules. You also need to
understand that the And rule is harder to satisfy in that it requires that two conditions be met.
Depending on what comes before or follows, each and/or effectively divides the list of ﬁ
filters into sets of ﬁ filters that are being evaluated. However, by being careful with ﬁ filters, you
can avoid combinations that are impossibly difﬁ cult to understand.
Suppose the ﬁ filters contained the comparisons shown in Table 10.1. The ﬁ rst And applies to
the Alexandria and VA ﬁ filters. The second And applies to the Hampton and VA ﬁ filters. This
set of ﬁ filters requires that records must be in Alexandria, VA, or in Hampton, VA.
TABLE 10.1 Understanding Or and And Operators
Finally, understand that it’s perfectly possible to set up ﬁ filters that make no logical sense.
Hence, Table 10.1 could have been set up with all of the Operators set to And . There would
be no matching records, of course. It’s up to you to examine the collection of resulting data
records to make sure that your logic is being applied as you think it should be.
Databases often contain duplicate records. When mailing or e-mailing, especially, you want
to avoid sending the same person duplicate messages. When sending invoices to large
companies, this can cause problems, especially if they are received and processed by different
people, resulting in double payment, and further paperwork downstream.
To ﬁ nd duplicates, click the Find duplicates link in the lower section of the Mail Merge
Recipients dialog box. Word displays the Find Duplicates dialog box, shown in Figure 10.20.
Remove the checks beside a valid duplicate to exclude it from the data merge. Look
carefully, however, because Word’s criteria for what constitutes a duplicate might be different
from your own.