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https://issues.apache.org/jira/browse/DERBY-4?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel#action_12497490
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A B commented on DERBY-4:
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> 1) An error message is added to InsertNode's initializer to reject
> the use of ORDER BY for INSERT ... VALUES statements 

Is there a technical reason for this restriction or is this just an incremental 
development and/or what-you're-willing-to-work-on-right-now restriction (which 
would be fine)?

I scanned through the comments for this issue and didn't see anything explicit 
about why a SELECT ... VALUES ... ORDER BY statement should throw an error, so 
I'm just wondering...

> "order by" is not supported for "insert ... select"
> ---------------------------------------------------
>
>                 Key: DERBY-4
>                 URL: https://issues.apache.org/jira/browse/DERBY-4
>             Project: Derby
>          Issue Type: New Feature
>          Components: SQL
>            Reporter: Christian d'Heureuse
>         Assigned To: Bryan Pendleton
>            Priority: Minor
>         Attachments: insertOrderBy.diff, insertOrderBy_v2.diff, samples.ij
>
>
> When filling a table with "insert ... select ...", "order by" cannot be 
> specified.
> There is not method to copy a table sorted into another table (except using 
> export/import). This would be useful to optimize performance for big tables, 
> or to create identity values that are ascending (related to another column).
> Example:
> create table temp1 (
>    s varchar(10));
> insert into temp1 values 'x','a','c','b','a';
> create table temp2 (
>    i integer not null
>       generated always as identity
>       primary key,
>    s varchar(10));
> insert into temp2 (s)
>    select s from temp1 order by s;
> --> Error: "order by" is not allowed.
> -- trying to use "group by" instead of "oder by":
> insert into temp2 (s)
>    select s from temp1 group by s;
> select * from temp2;
> --> "group by" did not sort the table.

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