Does Rowid change in Oracle?

Question

If you delete and reinsert a row with the Import and Export utilities, for example, then its rowid may change. If you delete a row, then Oracle may reassign its rowid to a new row inserted later.

Why does Rowid change in Oracle?

ROWID for index organized tables are different (they are called UROWID, I believe), because the physical location of the row can change during updates to the table (when tree nodes split or are joined).

Are Oracle Rowid sequential?

You're correct, Rowid is not sequential, just an internal unique identifier for each row of a table. If a row is deleted the Rowid may be re-used when a new row is inserted.

Is Rowid same as primary key?

The true primary key for a rowid table (the value that is used as the key to look up rows in the underlying B-tree storage engine) is the rowid. The PRIMARY KEY constraint for a rowid table (as long as it is not the true primary key or INTEGER PRIMARY KEY) is really the same thing as a UNIQUE constraint.

What is difference between ROW_NUMBER and Rowid?

ROWNUM is representative of the sequence allocated to any data retrieval bunch. ROWID is the permanent identity or address of a row. ROWNUM is a temporarily assigned sequence to a row. ROWID is a 16-digit Hexadecimal number in the format BBBBBBBB.

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