SQL to add column and comment in table in single command

Question

I am using Oracle 11g for my web application. I want to add a column and a comment to an existing table. I can do that easily with the below commands

ALTER TABLE product ADD product_description VARCHAR2(20) 

and

COMMENT ON COLUMN product.product_description       IS 'This is comment for the column'; 

But I want to do above task in single command. I searched on internet for a command to add a column and comment in a single command but I couldn't find. I wonder if this is possible. Any suggestions would be highly appreciated.

Answer 1

No, you can't.

There's no reason why you would need to. This is a one-time operation and so takes only an additional second or two to actually type and execute.

If you're adding columns in your web application this is more indicative of a flaw in your data-model as you shouldn't need to be doing it.

---

In response to your comment that a comment is a column attribute; it may seem so but behind the scenes Oracle stores this as an attribute of an object.

SQL> desc sys.com$  Name                                      Null?    Type  ----------------------------------------- -------- ----------------------------  OBJ#                                      NOT NULL NUMBER  COL#                                               NUMBER  COMMENT$                                           VARCHAR2(4000)  SQL> 

The column is optional and sys.col$ does not contain comment information.

I assume, I have no knowledge, that this was done in order to only have one system of dealing with comments rather than multiple.

Answer 2

You can use below query to update or create comment on already created table.

SYNTAX:

COMMENT ON COLUMN TableName.ColumnName IS 'comment text'; 

Example:

COMMENT ON COLUMN TAB_SAMBANGI.MY_COLUMN IS 'This is a comment on my column...';