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The term rowid refers to an integer
that defines the physical location of a row. The rowid of a row
in a nonfragmented table is a unique and constant value. Rows in fragmented
tables, in contrast, are not assigned a
rowid.
Important:
Use primary keys as a method of access in your applications
rather than rowids. Because primary keys are defined in the ANSI specification
of SQL, using primary keys to access data
makes your applications more portable.
Extended Parallel Server
The database server does not support rowids for fragmented tables.
End of Extended Parallel Server
Dynamic Server
To accommodate applications that must reference a rowid for a
fragmented table, Dynamic Server allows you to explicitly create a rowid column
for a fragmented table. However, Dynamic Server does not support the WITH ROWIDS clause
for typed tables.
To create the rowid column,
use the following SQL syntax:
- The WITH ROWIDS clause of the CREATE TABLE statement
- The ADD ROWIDS clause of the ALTER TABLE statement
- The INIT clause of the ALTER FRAGMENT statement
When you create the rowid column, the database server takes the
following actions:
- Adds the 4-byte unique value to each row in the table
- Creates an internal index that it uses to access the data in
the table by rowid
- Inserts a row in the sysfragments system
catalog table for the internal index
End of Dynamic Server
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