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What happens to view if we delete table?
Dropping a table removes the table definition from the data dictionary. All rows of the table are no longer accessible. All indexes and triggers associated with a table are dropped. All views and PL/SQL program units dependent on a dropped table remain, yet become invalid (not usable).
How is a table deleted?
To delete a table from the database. In Object Explorer, select the table you want to delete. Right-click the table and choose Delete from the shortcut menu. Deleting a table automatically removes any relationships to it.
How do I delete just a table?
Procedure
- Use the DELETE statement without specifying a WHERE clause. With segmented table spaces, deleting all rows of a table is very fast.
- Use the TRUNCATE statement. The TRUNCATE statement can provide the following advantages over a DELETE statement:
- Use the DROP TABLE statement.
How is a table deleted in SQL?
The deleted table stores copies of the affected rows during DELETE and UPDATE statements. During the execution of a DELETE or UPDATE statement, rows are deleted from the trigger table and transferred to the deleted table. The trigger table is the table on which the DML trigger runs.
Can you delete record from table using view?
DELETE Rule Rows from a join view can be deleted as long as there is exactly one key-preserved table in the join. If the view is defined with the WITH CHECK OPTION clause and the key preserved table is repeated, then the rows cannot be deleted from the view.
When to use SQL drop to delete a table?
The SQL DROP TABLE statement is used to remove a table definition and all the data, indexes, triggers, constraints and permission specifications for that table. NOTE − You should be very careful while using this command because once a table is deleted then all the information available in that table will also be lost forever.
When to delete data from a live table?
However, if the deleted data is more than a certain time period old (a year for example) you might decide to really delete it from the live tables but keep it in either an archive table or even just on back up should the user ever want it back. In this way you can keep the amount of data (live and recently deleted) to a minimum.
How do you delete a table in Excel?
Pressing the “Delete” key on the keyboard will not delete the entire selected table. It will only delete the contents of the cells. However, if you have selected at least one paragraph before or after the table as well as the table, the table can be deleted using the “Delete” key.
How do I delete the CUSTOMER table in SQL?
Completely delete the customer table (using the command DROP TABLE customer;), and re-create it from the customer_backup table (the same way we’ve created backup). The problem here is that you won’t be able to drop the table if it’s referenced in other tables. In our case, the call table has attribute call.customer_id related to customer.id.