Deleting Columns from a Table

Delete columns from a table when they are no longer needed to store data. When a column is deleted from the table in the database diagram, it and all the data it contains are deleted from the database.

Caution   This action cannot be undone once the database diagram or table is saved. The only way to restore a deleted column is to close the table or database diagram without saving changes.

To delete columns from a table

1. In your table or database diagram, select the column or columns you want to delete.
   
   
2. Right-click the column and choose Delete Column from the shortcut menu.
   
   
3. If the column participates in a relationship, a message prompts you to confirm the deletion of the selected columns and their relationships. Choose OK.

If the column does not participate in a check constraint, then the column, any constraints attached to it, any relationships it participates in, and any data contained in the column are removed from the database and the diagram. They are deleted from the database when you save the table or database diagram.  If the column does participate in a check constraint, the database server will reject your modification when you save your work.  That is, the commit operation will fail.  To delete a column that participates in a check constraint, you must first modify or remove the check constraint before deleting the column.

See Also

Deleting a Table from a Database Diagram and the Database | Inserting Columns into a Table | Tables