[DERBY-1515] Provide ALTER TABLE functionality to change a column's data type

• Type: Improvement
• Status: Closed
• Priority: Minor
• Resolution: Won't Fix
• Affects Version/s: 10.1.1.0, 10.1.2.1, 10.1.3.1, 10.2.1.6
• Component/s: Documentation, SQL
• Assignee: Unassigned
• Reporter: Bryan Pendleton
• Created: 16/Jul/06 16:27
• Updated: 01/Jul/09 00:34
• Resolved: 09/Nov/06 00:43

Description

Derby should provide a feature which allows a user to change the data type of an existing column in an existing table.

Currently, there exists the statement:

ALTER TABLE tablename ALTER COLUMN columnname SET DATA TYPE datatype

However, this statement currently only allows increasing the length of a VARCHAR column. You are not allowed to decrease the width or to change the data type.

It would be nice if this restriction could be lifted, and the datatype could be changed.

Issue Links

• is related to: DERBY-396 Support for ALTER STATEMENT to DROP , MODIFY, RENAME a COLUMN
• relates to: DERBY-396 Support for ALTER STATEMENT to DROP , MODIFY, RENAME a COLUMN