drop usage in oracle

DROP Usage in Oracle

DROP Statement

The DROP statement allows you to delete various objects from the database. These objects include:

• Table
• View
• Index
• Process
• Function

Grammar

The general syntax of the DROP statement is as follows:

<code class="sql">DROP <object_type> <object_name>;</code>

Among them:

• ## is The type of object to delete.
• is the name of the object to be deleted.

CASCADE clause

The CASCADE clause can be used to cascade delete other database objects that depend on this object. For example, if you drop a table, the CASCADE clause can also drop the table's indexes.

<code class="sql">DROP TABLE employees CASCADE;</code>

Usage

The DROP statement can be used for the following purposes:

Delete objects that are no longer needed or are obsolete.
• Reorganize the database structure.
• Release storage space.

Notes

When using the DROP statement, please note the following:

The DROP operation is irreversible. Once an object is deleted, it cannot be restored.
• Before deleting an object, make sure it is no longer needed.
• If you want to delete an object that has dependencies, consider using the CASCADE clause.

Example

The following example demonstrates how to use the DROP statement to delete a table:

<code class="sql">DROP TABLE employees;</code>

The following example demonstrates how to use the CASCADE clause to delete a table Table and its index:

<code class="sql">DROP TABLE employees CASCADE;</code>

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