How do I fix Ora-01779?
How do I fix Ora-01779?
Action: Modify the underlying base tables directly. In your case, the ORA-01779 results because the update statement is malformed (by using an in-line view on two tables) and you want to issue the SQL update directly against one individual table, not the two tables that are specified in your DML syntax.
How do you resolve ORA-01779 Cannot modify a column which maps to a non key preserved table?
This ORA-01779 errors are related with the attempt was made to insert or update columns of a join view which map to a non-key-preserved table. You can Modify the underlying base tables directly and Try updating the tables directly. Or You can use work around is to use MERGE to do this.
What is key preserved table in Oracle?
A key-preserved table is a base table with a one-to-one row relationship with the rows in the view, via either the primary key or a unique key. In the example above, the cars table is a key-preserved table.
What is updatable view?
An updatable view is a special case of a deletable view. A deletable view becomes an updatable view when at least one of its columns is updatable. A column of a view is updatable when all of the following rules are true: The view is deletable.
What is an updatable view in Oracle?
An updatable view is one you can use to insert, update, or delete base table rows. You can create a view to be inherently updatable, or you can create an INSTEAD OF trigger on any view to make it updatable.
How do I check if a view is updatable?
Checking updatable view information You can check if a view in a database in updatable by querying the is_updatable column from the views table in the information_schema database.
What is updatable view and non updatable view?
It means that the server always knows whether a view is updatable. If a view is not updatable, statements such UPDATE , DELETE , and INSERT are illegal and are rejected. (Even if a view is updatable, it might not be possible to insert into it, as described elsewhere in this section.)
What makes a view updatable?
A deletable view becomes an updatable view when at least one of its columns is updatable. A column of a view is updatable when all of the following rules are true: The view is deletable. The column resolves to a column of a table (not using a dereference operation) and the READ ONLY option is not specified.
How do you make a non updatable view?
To be more specific, a view is not updatable if it contains any of the following:
- Aggregate functions (SUM(), MIN(), MAX(), COUNT(), and so forth)
- DISTINCT GROUP BY HAVING UNION or UNION ALL Subquery in the select.
- list Certain joins.
- Nonupdatable view in the FROM clause.
- A subquery in the WHERE.
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