Table of Contents
What happens when you delete a base table that belongs to a view?
Deleting a row in a table will affect the results from regular views. Views are not executed when they are created. They are executed when they are referenced. Each time you reference the view in the query, it is run again.
Does deleting the table delete view?
table is physical representation. In case you delete the table then there is no chance of existing view. In short there is chance of existing logical things without having physicaL thing.
What happens to materialized view if table is dropped?
If you drop a materialized view, then any compiled requests that were rewritten to use the materialized view will be invalidated and recompiled automatically. If the materialized view was prebuilt on a table, then the table is not dropped, but it can no longer be maintained by the materialized view refresh mechanism.
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.
What command is used to delete the data from the table without deleting the table structure?
TRUNCATE Command is a Data Definition Language operation. It is used to remove all the records from a table. It deletes all the records from an existing table but not the table itself. The structure or schema of the table is preserved.
Which of the following command is used to delete a table in SQL?
The drop table command
The drop table command is used to delete a table and all rows in the table. To delete an entire table including all of its rows, issue the drop table command followed by the tablename.
Can data be deleted from view?
Well you can delete from a view if that is what you are asking, but you can’t have a view that deletes information. The view is a portion of data from the underlying tables. Provided that you have permissions, you can do the same data manipulation in views that you can do to a table directly.
Can we update delete in view if yes then will it be deleted from main table?
Yes, possible to insert,update and delete to view. view is a virtual table.
Can we drop a table that has dependent views on it?
Only its owner may destroy a table. (CASCADE will remove a dependent view entirely, but in the foreign-key case it will only remove the foreign-key constraint, not the other table entirely.)
How delete all data from table in Oracle?
Oracle DELETE
- First, you specify the name of the table from which you want to delete data.
- Second, you specify which row should be deleted by using the condition in the WHERE clause. If you omit the WHERE clause, the Oracle DELETE statement removes all rows from the table.
What command is used to delete the data?
DELETE is a DML(Data Manipulation Language) command and is used when we specify the row(tuple) that we want to remove or delete from the table or relation….Difference between DELETE and TRUNCATE.
S.NO | Delete | Truncate |
---|---|---|
9. | The delete can be used with indexed views. | Truncate cannot be used with indexed views. |