Can we delete from view in SQL?

How do I delete a row from a view in SQL?

If you want a row to disappear from a view, you need to either delete the data from the real tables behind the view, or alter the view-creating SQL so that that particular row won’t be shown in the view.

Can you delete from a view SQL?

You can insert, update, and delete rows in a view, subject to the following limitations: If the view contains joins between multiple tables, you can only insert and update one table in the view, and you can’t delete rows. … You can’t modify data in views that use GROUP BY or DISTINCT statements.

Can we delete data from view in Oracle?

When you delete rows from an updatable view, Oracle Database deletes rows from the base table. You cannot delete rows from a read-only materialized view. If you delete rows from a writable materialized view, then the database removes the rows from the underlying container table.

Can you edit a view in SQL?

The ALTER VIEW command allows you to modify a view. A view is based on the result set from a query consisting of a SELECT statement or a UNION of two or more SELECT statements. … To determine if a specified view exists in the current namespace, use the $SYSTEM. SQL.

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Does deleting from a view delete from the table?

Yes, it will. The only thing to watch out for, is permissions. Some views are updatable. That is, you can use them in statements such as UPDATE, DELETE, or INSERT to update the contents of the underlying table.

How do I remove data from view?

SQL VIEW can be created by a SQL query by joining one or more table. If you want to delete a SQL view, It is done by SQL DROP command you should use the following syntax: SQL DROP VIEW syntax: DROP VIEW view_name.

Can we update or delete records from the view?

Yes, possible to insert,update and delete to view. view is a virtual table. Same Perform as insert,update,delete query.. A view can be defined as a virtual table or a stored query and the data accessible through a view is not stored in the database as a distinct object.

What are the problems associated with updating views?

3. Problems in updating Views:

  • A view with a single defining table is updatable if the view attributes contain the primary key of the base relation, as well as all attributes with the NOT NULL constraint that do not have default values specified.
  • It is generally not possible to update views defined on multiple tables.

How can you tell if a view is updatable?

If the view has not been defined using groups and aggregate functions. If the view does not have any distinct clause in its definition. If the view that is supposed to be updated is based on another view, the later should be updatable. If the definition of the view does not have any sub queries.

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What is the syntax for delete the view?

We can delete or drop a View using the DROP statement. Syntax: DROP VIEW view_name; view_name: Name of the View which we want to delete.

Is commit required after delete in Oracle?

Oracle Database issues an implicit COMMIT before and after any data definition language (DDL) statement. Oracle recommends that you explicitly end every transaction in your application programs with a COMMIT or ROLLBACK statement, including the last transaction, before disconnecting from Oracle Database.

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