Software QA (13)
SQL Server (1)
How To Delete a Column in an Existing Table
How To Delete a Column in an Existing Table? - Oracle DBA FAQ - Managing Oracle Database Tables
If you have an existing column in a table and you need that column any more, you can delete it with ALTER TABLE ... DROP COLUMN statement. Here is an example SQL script:
SQL> CREATE TABLE emp_dept_90 2 AS SELECT * FROM employees WHERE department_id=90; Table created. SQL> SELECT last_name FROM emp_dept_90; LAST_NAME ------------------------- King Kochhar De Haan SQL> ALTER TABLE emp_dept_90 DROP COLUMN last_name; Table altered. SQL> SELECT last_name FROM emp_dept_90; ERROR at line 1: ORA-00904: "LAST_NAME": invalid identifier
As you can see the column "last_name" is gone.
2007-05-03, 4796👍, 0💬
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