Does dropping an index lock the table?

Does dropping an index lock the table?

A normal DROP INDEX acquires exclusive lock on the table, blocking other accesses until the index drop can be completed. With this option, the command instead waits until conflicting transactions have completed. Refuse to drop the index if any objects depend on it.

Do we need to drop index before dropping table?

3 Answers. Yes, it does. However, if you have foreign key constraints such as RESTRICT that ensure referential integrity with other tables, you’ll want to drop those keys prior to dropping or truncating a table. Yes it would drop the index.

What is DROP TABLE if exists?

The DROP TABLE statement deletes the specified table, and any data associated with it, from the database. The IF EXISTS clause allows the statement to succeed even if the specified tables does not exist. Attempting to drop the table before dropping the procedure will result in an error.

Does index get dropped when table is dropped Oracle?

Specify the name of the table to be dropped. Oracle Database automatically performs the following operations: All rows from the table are dropped. All table indexes and domain indexes are dropped, as well as any triggers defined on the table, regardless of who created them or whose schema contains them.

Does the view exist if the table is dropped from the database?

Question: Does the SQL View exist if the table is dropped from the database? Answer: Yes, in Oracle, the SQL VIEW continues to exist even after one of the tables (that the SQL VIEW is based on) is dropped from the database.

Which dependent objects are dropped when a table is dropped?

All table indexes and domain indexes are dropped, as well as any triggers defined on the table, regardless of who created them or whose schema contains them. If table is partitioned, then any corresponding local index partitions are also dropped.

Does drop table drop views?

Any view on a table that is dropped by using DROP TABLE must be dropped explicitly by using DROP VIEW. When executed against an indexed view, DROP VIEW automatically drops all indexes on a view.

What happens when you drop an index in Oracle?

When you drop an index, Oracle Database invalidates all objects that depend on the underlying table, including views, packages, package bodies, functions, and procedures. When you drop a global partitioned index, a range-partitioned index, or a hash-partitioned index, all the index partitions are also dropped.

What’s the difference between disabling and dropping indexes?

The biggest difference between disabling and dropping a nonclustered index is whether the index definition stays around. Make sure you carefully weigh your options before performing either action, and always have a way to recreate the index available. Read all about it: We’ve got tons of free articles.

What happens when you drop a clustered index?

To drop a clustered or nonclustered index, issue a DROP INDEX command. When you do this, the metadata, statistics, and index pages are removed. If you drop a clustered index, the table will become a heap. Once an index has been dropped, it can’t be rebuilt – it must be created again.

What happens when you disable a disabled index?

The data in the table still exists, but will be inaccessible for anything other than a drop or rebuild operation. All related nonclustered indexes and views are also unavailable. Foreign key constraints that reference the table are disabled. Queries against the table will fail. I want it back! How to re-enable a disabled index