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https://issues.apache.org/jira/browse/DERBY-481?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=12582121#action_12582121
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Daniel John Debrunner commented on DERBY-481:
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Since DeterministicCharacteristic  is an independent feature to generated 
columns should it be its own Jira issue.
If not we may land in a similar situation to DERBY-2109 where independent 
functionality is implemented but no record exists in Jira.

> implement SQL generated columns
> -------------------------------
>
>                 Key: DERBY-481
>                 URL: https://issues.apache.org/jira/browse/DERBY-481
>             Project: Derby
>          Issue Type: New Feature
>          Components: SQL
>    Affects Versions: 10.0.2.1
>            Reporter: Rick Hillegas
>         Attachments: GeneratedColumns.html
>
>
> Satheesh has pointed out that generated columns, a SQL 2003 feature, would 
> satisfy the performance requirements of Expression Indexes (bug 455). 
> Generated columns may not be as elegant as Expression Indexes, but they are 
> easier to implement. We would allow the following new kind of column 
> definition in CREATE TABLE and ALTER TABLE statements:
>     columnName GENERATED ALWAYS AS ( expression )
> If expression were an indexableExpression (as defined in bug 455), then we 
> could create indexes on it. There is no work for the optimizer to do here. 
> The Language merely has to compute the generated column at INSERT/UPDATE time.

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