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Inserting A Page Break Following A Specific Number of Rows in A Table

You can use the Ceiling function to group the rows within a table and insert a page break at the end of each group.
The Ceiling function returns the smallest number that is not less than the argument.
For example, to add a page break after every 30 rows, you would use the following expression to group the rows:

The RDL that describes the group would resemble the following: