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Using the ADD ROWIDS Keywords (IDS)

Use the ADD ROWIDS keywords to add a new column called rowid to a fragmented table. (Fragmented tables do not contain the hidden rowid column by default.) When you add a rowid column, the database server assigns a unique number to each row that remains stable for the life of the row. The database server creates an index that it uses to find the physical location of the row. After you add the rowid column, each row of the table contains an additional 4 bytes to store the rowid value.

Tip:
Use the ADD ROWIDS clause only on fragmented tables. In nonfragmented tables, the rowid column remains unchanged. It is recommended that you use primary keys as an access method rather than exploiting the rowid column.

For additional information about the rowid column, refer to your IBM Informix Administrator's Reference.

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