Op 4-12-2012 23:08, Knut Anders Hatlen schreef:
Kim Haase <[email protected]> writes:
Should I file a doc JIRA to clarify that ALTER TABLE adds the new
column at the end?
That would be great.
It seems obvious, but perhaps we should clarify
that a programmatic attempt to change the data type of a column will
still result in the changed column being appended.
I notice it is possible to change the data type of a column using
"ALTER TABLE ALTER column-name SET DATA TYPE", but you can only change
the type to VARCHAR or VARCHAR FOR BIT DATA. Do you know why that is?
We probably only allow changing the maximum length of columns that
already are VARCHAR or VARCHAR FOR BIT DATA. Since changing the maximum
length can be done in the table meta-data without changing the stored
format of each value, that's easier to support than the general case.
For example, changing the type from INT to DOUBLE would require an
update of every row in the table, since they have different formats.
That's my guess, at least.
Hi Knut,
Thanks for looking at this.
As you described it seemed to be related to the Order By in the Select
phrase of the bulk Insert.
Therefore I removed the Order By of the Select and now the bulk Insert
went well.
The Order By was not necessary for my conversion.
Out of convenience I used copy/paste to the Insert statement.
I hope my issue helped to clarify the Insert procedure in Derby.
Kind regards,
Harm-Jan Zwinderman
