Extent sizes for table fragments

When you fragment an existing table, you might want to adjust the next-extent size because each fragment requires less space than the original, unfragmented table.

If the unfragmented table was defined with a large next-extent size, the database server uses that same size for the next-extent on each fragment, which results in over-allocation of disk space. Each fragment requires only a proportion of the space for the entire table.

For example, if you fragment the preceding big_one sample table across five disks, you can alter the next-extent size to one-fifth the original size. The following example changes the next-extent size to one-fifth of the original size:
ALTER TABLE big_one MODIFY NEXT SIZE 2;

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