[DERBY-3350] SQL CAST always marks its type as nullable even if the expression to be cast is not nullable

• Type: Bug
• Status: Closed
• Priority: Minor
• Resolution: Fixed
• Affects Version/s: 10.0.2.0, 10.0.2.1, 10.1.1.0, 10.1.2.1, 10.1.3.1, 10.2.1.6, 10.2.2.0, 10.3.1.4, 10.3.2.1, 10.4.1.3
• Fix Version/s: 10.4.1.3
• Component/s: SQL
• Assignee: Daniel John Debrunner
• Reporter: Daniel John Debrunner
• Created: 24/Jan/08 19:55
• Updated: 29/Jan/08 19:27
• Resolved: 29/Jan/08 19:27

Description

Can be exposed as a column's type in a ResultSet being nullable when in reality it can never be null.

Can impact performance as the SQL compiler can general optimal paths with correct nullability, e.g. a non-null INTEGER expression does not need normalization if being stored in a non-null INTEGER column, routine calling can be optimized for a RETURNS NULL ON NULL INPUT function if the inputs are never null.