Deleting a field from a table in Oracle requires the following steps: Determine the field to be deleted. Use the ALTER TABLE table_name DROP COLUMN column_name statement. Commit the changes. After a field is deleted, it will not be restored and dependencies need to be checked and adjusted.
How to delete a field from a table in Oracle
Deleting a field from an Oracle table is a common task that can Complete the following steps:
1. Determine the field to be deleted
Determine the name of the field to be deleted from the table.
2. Use the ALTER TABLE statement
Use the following syntax to write the ALTER TABLE statement:
ALTER TABLE table_name DROP COLUMN column_name;
Where:
-
table_name
is the name of the table from which the field is to be deleted. -
column_name
is the name of the field to be deleted.
Example:
To delete the email
field from the table named employees
, you can run the following Statement:
ALTER TABLE employees DROP COLUMN email;
3. Commit changes
Use the COMMIT statement to commit changes to the table.
COMMIT;
Note:
- After a field is deleted, it cannot be restored.
- If the field contains foreign keys or constraints, they must be deleted or modified first.
- After removing a field, any views, triggers, or other dependencies in the table need to be checked and adjusted accordingly.
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