Can Rowid be used as primary key?

Question

You should not use ROWID as the primary key of a table. 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.

How do you use Rowid?

ROWID is the physical location of a row. Consequently it is the fastest way of locating a row, faster even than a primary key lookup. So it can be useful in certain types of transaction where we select some rows, store their ROWIDs and then later on use the ROWIDs in where clauses for DML against those same rows.

Can we use Rowid in WHERE clause?

Usage. You can use a ROWID value to refer to a row in a table in the WHERE clauses of a query.

What is difference between Rownum and Rowid?

In sum, the difference between ROWNUM and ROWID is that ROWNUM is temporary while ROWID is permanent. Another difference is that ROWID can be used to fetch a row, while ROWNUM only has meaning within the context of a single SQL statement, a way of referencing rows within a fetched result set.

Is Rowid sequential Oracle?

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.

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