What does drop mean in sql?

The DROP command in SQL is used to delete database objects (such as tables, views, indexes), including the following uses: Delete objects that are no longer needed or are obsolete. Delete incorrect or damaged objects. Modify the database structure.

The meaning of DROP in SQL

DROP is used in SQL to delete database objects (such as tables, views, index) command.

Purpose

The DROP command is mainly used in the following situations:

• Delete objects that are no longer needed or obsolete.
• Delete incorrect or damaged objects.
• Modify the database structure.

Syntax

The syntax of the DROP command is as follows:

DROP [OPTION]  ;

Among them:

• OPTIONOptional, specifies the behavior of the delete operation. For example,CASCADEis used to cascade delete related objects.
• Specifies the object type to be deleted, such asTABLE,VIEW,INDEX.
• Specifies the name of the object to be deleted.

Note

• The DROP operation is irreversible, so use it with caution.
• Be sure to back up your data before deleting the table.
• If you want to drop tables associated with other objects, use theCASCADEoption.
• If the object does not exist, the DROP command will generate an error.

Example

Delete the table namedcustomers:

DROP TABLE customers;

Delete the table namedcustomer_index# Index of ##:

DROP INDEX customer_index;

my_view:

DROP VIEW my_view;

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