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https://issues.apache.org/jira/browse/DERBY-4555?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15339523#comment-15339523
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Bryan Pendleton commented on DERBY-4555:
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Yes, I like the suggested name of SYSCS_IMPORT_TABLE_BULK, too.
Regarding the request to parse columns by header-name, I think we
should look at that item as part of our work here, too.
But first I think we should complete the first phase, of getting
the new procedure name in place, writing the tests, etc.
Then we can take a look at doing the header-name parsing, and see
if we think it is hard or easy. I am not sure I understand the
proposed approach clearly. But there are some details: is the name
matching case-sensitive? Or case-exact? Does the matching care
about white-space? What if the column headers are these new
multi-line sort of headers? what if a column name should contain
a comma, or a space, or some other sort of special character?
I don't think these issues are particularly unsolvable, but I
would like to spend some time ensuring we have a clear and
precise description of the problem we're attempting to solve.
Also, since we're talking about it: so far, we've been working
on providing a new alternate system procedure for SYSCS_IMPORT_TABLE,
but the column-name/header-name issue involves SYSCS_IMPORT_DATA,
not SYSCS_IMPORT_TABLE.
I think that, assuming we can work out the final details of
providing a SYSCS_IMPORT_TABLE_BULK alternative to SYSCS_IMPORT_TABLE,
we'll also want to provide a SYSCS_IMPORT_DATA_BULK alternative
to SYSCS_IMPORT_DATA.
So maybe what we have here are several sub-tasks:
1) Create new SYSCS_IMPORT_TABLE_BULK procedure, with extra
(varargs?) argument at the end to support multi-line headers
2) Create new SYSCS_IMPORT_DATA_BULK procedure, similar to (1)
3) Enhance COLUMNINDEXES parsing for SYSCS_IMPORT_DATA_BULK
procedure, to support recognition of columns by header-name
as well as by index number
4) Add documentation for the new system procedures
We can use JIRA's sub-task functionality to track these sub-tasks
separately, then we'll mark 4555 as resolved once the entire
set of tasks is complete.
> Expand SYSCS_IMPORT_TABLE to accept CSV file with header lines
> --------------------------------------------------------------
>
> Key: DERBY-4555
> URL: https://issues.apache.org/jira/browse/DERBY-4555
> Project: Derby
> Issue Type: Improvement
> Components: Miscellaneous
> Reporter: Yair Lenga
> Assignee: Danoja Dias
> Attachments: NoVarargs.diff, Varargs.diff,
> addNewSystemProcedure_1.diff, gotException.diff, hardCoded.diff, latest.diff,
> noHeaderLines.csv, petlist.csv, petlist.csv, petlist.csv, repro.java,
> repro.java, repro.java, skipHeaders.diff
>
>
> The SYSCS_IMPORT_TABLE (and SYSCS_IMPORT_DATA) function allow import of data
> from external resources. In general, they can process CSV files that created
> with various tools - with one exception: the header line.
> While there is no accepted standard, most tools will include a header line in
> the CSV file with column names. This convention is supported in Excel and
> many other tools.
> My Request: extend the SYSCS_IMPORT_TABLe and SYSCS_IMPORT_DATA (and other
> related procedures) to include an extra indicator for the number of header
> lines to be ignored.
> As an extra bonus it will be help is the SYSCS_IMPORT_DATA will accept column
> names (instead of column indexes) in the 'COLUMNINDEXES' arguments. E.g., it
> should be possible to indicate COLUMNINDEXES of '1,3,sales,5,'. This feature
> will make it significantly easier to handle cases where the external input
> files is extended to include additional columns.
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