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much from being stored in a compressed table; the double compression can waste CPU cycles for little or no space savings.

The overflow pages are of the same size as other pages. A row containing ten columns stored offpage

occupies ten overflow pages, even if the total length of the columns is only 8K bytes. In an

uncompressed table, ten uncompressed overflow pages occupy 160K bytes. In a compressed table

with an 8K page size, they occupy only 80K bytes. Thus, it is often morę

efficient to use compressed

table format for tables with long column values.

Using a 16K compressed page size can reduce storage and l/O costs for

BLOB, VARCHAR, or TEXT

columns, because such data often compress well, and might therefore require fewer overflow pages,

even though the B-tree nodes themselves take as many pages as in the uncompressed form.