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sqloracleoracle11g

SQL to add column and comment in table in single command

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.

Solution

  • 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.