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From Kasper Sørensen <i.am.kasper.soren...@gmail.com>
Subject Re: Create a CSV in a empty file
Date Wed, 16 Jul 2014 21:22:42 GMT
I'm just now simultaniously looking into the MM csv code ... I get the
feeling you're maybe a bit in untested territory. At least it seems that
CsvDataContextTest does not exhibit a lot of test cases around having no
column headers ... Might be we need your feedback here if there are issues.


2014-07-16 23:19 GMT+02:00 Kasper Sørensen <i.am.kasper.sorensen@gmail.com>:

> Ah, you want a header-less CSV file? You then need to instantiate your
> CsvDataContext with a CsvConfiguration that
> specifies CsvConfiguration.NO_COLUMN_NAME_LINE as the
> 'columnNameLineNumber' property. If you otherwise want defaults, that would
> be like this:
>
> new CsvConfiguration(CsvConfiguration.NO_COLUMN_NAME_LINE);
>
>
> 2014-07-16 23:14 GMT+02:00 Júnior <fjunior87@gmail.com>:
>
> Right, what I'd like to know is to create the table without the header, I
>> think the only way would be changing the CsvCreateTableBuilder.
>> Thanks,
>>
>>
>>
>> 2014-07-16 18:12 GMT-03:00 Kasper Sørensen <
>> i.am.kasper.sorensen@gmail.com>:
>>
>> > Hmm actually I just now realized that you can completely omit the Drop
>> > Table part ... if you use create table on an empty file, it will simply
>> > create the header.
>> >
>> >
>> > 2014-07-16 23:10 GMT+02:00 Kasper Sørensen <
>> i.am.kasper.sorensen@gmail.com
>> > >:
>> >
>> > > Yes, you do that while creating the table. Like this:
>> > >
>> > >         CsvDataContext dc = ...;
>> > >         dc.executeUpdate(new UpdateScript() {
>> > >             @Override
>> > >             public void run(UpdateCallback callback) {
>> > >                 callback.dropTable(dc.getDefaultSchema().getTable(0));
>> > >
>> > >                 callback.createTable(dc.getDefaultSchema(),
>> > > "newtable").withColumn("foo").withColumn("bar").execute();
>> > >             }
>> > >         });
>> > >
>> > > (replace with your own column names of course)
>> > >
>> > >
>> > > 2014-07-16 23:04 GMT+02:00 Júnior <fjunior87@gmail.com>:
>> > >
>> > > Hi Kasper,
>> > >>
>> > >> thanks for your reply, but what about the columns?
>> > >>
>> > >> Do I need to add columns to this newly created table?
>> > >>
>> > >> Att.
>> > >>
>> > >>
>> > >> 2014-07-16 18:00 GMT-03:00 Kasper Sørensen <
>> > >> i.am.kasper.sorensen@gmail.com>:
>> > >>
>> > >> > Hi there,
>> > >> >
>> > >> > There is a little known trick to get around that issue, so I guess
>> > it's
>> > >> a
>> > >> > very fair question.
>> > >> >
>> > >> > The trick is to first do a drop table, and then a new create table.
>> > >> >
>> > >> > When MM is initialized with an existing empty file, it will
>> determine
>> > >> that
>> > >> > there IS a table, since the file is there, but that table has
no
>> > >> columns,
>> > >> > because the file does not define any columns. Maybe it's a bit
>> silly
>> > - I
>> > >> > actually think that's worth discussing ... But the reason it is
>> there
>> > >> is I
>> > >> > guess to indicate that at least the file is there, it's not a
>> > >> non-existing
>> > >> > file (in which case there would not be any table).
>> > >> >
>> > >> > Best regards,
>> > >> > Kasper
>> > >> >
>> > >> >
>> > >> > 2014-07-16 21:37 GMT+02:00 Júnior <fjunior87@gmail.com>:
>> > >> >
>> > >> > > Hi,
>> > >> > >
>> > >> > > I'm trying to use the metamodel to write on an empty csv,
>> > >> > >
>> > >> > > But I'm getting errors saying that there is no column.
>> > >> > >
>> > >> > > I was able to do that calling create table with a different
name
>> > from
>> > >> the
>> > >> > > file.
>> > >> > > Then added the columns.
>> > >> > >
>> > >> > > I worked, but it created the header line with the column
names,
>> > would
>> > >> it
>> > >> > be
>> > >> > > possible to do that without adding the column names in the
csv
>> file?
>> > >> > >
>> > >> > > Att.
>> > >> > > --
>> > >> > > Francisco Ribeiro
>> > >> > > *SCEA|SCJP|SCWCD|IBM Certified SOA Associate*
>> > >> > >
>> > >> >
>> > >>
>> > >>
>> > >>
>> > >> --
>> > >> Francisco Ribeiro
>> > >> *SCEA|SCJP|SCWCD|IBM Certified SOA Associate*
>> > >>
>> > >
>> > >
>> >
>>
>>
>>
>> --
>> Francisco Ribeiro
>> *SCEA|SCJP|SCWCD|IBM Certified SOA Associate*
>>
>
>

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