Discuss row chaining, how does it happen? How ca

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Discuss row chaining, how does it happen? How can you reduce it? How do you correct it?

Level: high
Expected answer: Row chaining occurs when a VARCHAR2 value is updated and the length of the new value is longer than the old value and won?t fit in the remaining block space. This results in the row chaining to another block. It can be reduced by setting the storage parameters on the table to appropriate values. It can be corrected by export and import of the effected table.

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