Hi Mike, It is theoretically possible but I don't have an example of the syntax. As you've probably figured out, Drill vectors have both a type and data mode. The mode is either NULLABLE or REPEATED if I remember correctly. Thus, you could tell Drill via the inline schema that the data mode for a given field is REPEATED and that would be the Drill equivalent of an Array. I've never actually done this, so I don't really know if it would work for inline schemata but I'd assume that it would.
I'll do some digging to see whether I have any examples of this.
Best,
--C
> On Aug 14, 2023, at 3:36 PM, Mike Beckerle <mbecke...@apache.org> wrote:
>
> I'm trying to get my Drill SQL queries to produce the right thing from XML.
>
> A major thing that you can't easily infer from looking at just XML data is
> what is an array. XML lacks an array starting indicator.
>
> Is there an inline schema notation in the Drill Query language for
> array-ness, so that one can inform Drill what is an array?
>
> For example this provides simple types for all the fields directly in the
> query.
>
> @Test
>
> public void testSimpleProvidedSchema() throws Exception {
>
> String sql = "SELECT * FROM table(cp.`xml/simple_with_datatypes.xml`
> (type => 'xml', schema " +
>
> "=> 'inline=(`int_field` INT, `bigint_field` BIGINT, `float_field`
> FLOAT, `double_field` DOUBLE, `boolean_field` " +
>
> "BOOLEAN, `date_field` DATE, `time_field` TIME, `timestamp_field`
> TIMESTAMP, `string_field`" +
>
> " VARCHAR, `date2_field` DATE properties {`drill.format` =
> `MM/dd/yyyy`})'))";
>
> RowSet results = client.queryBuilder().sql(sql).rowSet();
>
> assertEquals(2, results.rowCount());
>
>
> Can one also tell Drill what fields or child elements are arrays?
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