Update a table with itself, with one SQL statement description
Sometimes you may need to update a table with its own data, typically when rows contain a link to values stored in other rows. The example SQL and narrative illustrate how to do this via an Update statement with a subquery.
File List:
update_table_with_itself.sql
7Kb
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Code Library
) : This PL/SQL block deletes duplicate rows in a table, using a FOR UPDATE cursor and program control. Clear, concise comments are interspersed in the code. A test execution is included.