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http://issues.apache.org/jira/browse/DERBY-396?page=comments#action_12357062 ] 

Scott MacDonald commented on DERBY-396:
---------------------------------------

I am presently working on the Rename and Drop column issues.

As discussed previously on this Comment page, should the Oracle and Postgres 
syntax for renaming and dropping columns be followed?

The syntax is:

ALTER TABLE <table_name> DROP COLUMN <table_name>

ALTER TABLE <table_name> RENAME COLUMN <old_name> TO <new_name>


I have also been browsing documentation for Oracle, Postgres, and DB2 and doing 
some simple testing in DB2 regarding contstraints on renaming and dropping 
columns.

I have found that any column can be dropped, so long as it does not affect the 
referential integrity of the table or any other tables in the database (ie. as 
long as the column is not a primary or foreign key).

I have also found that any column can be renamed so long as the new column name 
is not already the name of another column in the table.  The new column name 
must also be either an ordinary or delimited identifier.

If anybody has any comments on these topics before I begin implementation, I 
would like to hear them.

Thanks,
Scott

> Support for ALTER STATEMENT to DROP ,  MODIFY, RENAME a COLUMN
> --------------------------------------------------------------
>
>          Key: DERBY-396
>          URL: http://issues.apache.org/jira/browse/DERBY-396
>      Project: Derby
>         Type: New Feature
>   Components: SQL
>  Environment: LINUX 
>     Reporter: Kumar Matcha
>     Assignee: Scott MacDonald
>     Priority: Critical

>
> Alter Statement should support  dropping a column, modifying a column to a 
> different data type , rename a column.

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