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After creating joins, one or more join trees appear on the Calculated, Pre-Filters, and Display tabs. For example, if you join tables "A" and "B," "B" and "C," then join tables "D" and "E," the result is two join trees. Columns of table "A" and table "C" may appear in the same report because their tables belong to the same join tree. Tables "A" and "D" are said to be unjoined—their columns may not be compared or appear in the same report. Tables that are not joined appear individually along with the join trees.
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