I suppose the separator would have to be known to the client somehow (perhaps as metadata) - you'd have the same problem in the opposite direction if the result were a list right? You wouldn't be able to concatenate the parts together without knowing a safe separator to use.
On Thu, Sep 22, 2022, at 14:23, Gavin Ray wrote: > Wait, what happens if a datasource's spec allows dots as valid identifiers? > > On Thu, Sep 22, 2022 at 2:22 PM Gavin Ray <ray.gavi...@gmail.com> wrote: > >> Ah okay, yeah that's a reasonable angle too haha >> >> >> On Thu, Sep 22, 2022 at 1:59 PM David Li <lidav...@apache.org> wrote: >> >>> Frankly it was from a "not drastically refactoring things" perspective :) >>> >>> At least for Arrow: list[utf8] is effectively a utf8 array with an extra >>> array of offsets, so there's relatively little overhead. (In particular, >>> there's not an extra allocation per array; there's just an overall >>> allocation of a bitmap/offsets buffer.) >>> >>> On Thu, Sep 22, 2022, at 13:46, Gavin Ray wrote: >>> > I suppose you're thinking from a memory/performance perspective right? >>> > Allocating a dot character is a lot better than allocating multiple >>> arrays >>> > >>> > Yeah I don't see why not -- this could even be a library internal where >>> the >>> > fact that it's dotted is an implementation detail >>> > Then in the Java implementation or whatnot, you can call >>> > ".getFullyQualifiedTableName()" which will do the allocating parse to a >>> > List<String> for you, or whatnot >>> > >>> > The array was mostly for convenience's sake (our API is JSON and not >>> > particularly performance-oriented) >>> > >>> > On Thu, Sep 22, 2022 at 1:40 PM David Li <lidav...@apache.org> wrote: >>> > >>> >> Ah, interesting… >>> >> >>> >> A self-recursive schema wouldn't work in Arrow's schema system, so it'd >>> >> have to be the latter solution. Or, would it work to have a dotted >>> name in >>> >> the schema name column? Would parsing that back out (for applications >>> that >>> >> want to work with the full hierarchy) be too much trouble? >>> >> >>> >> On Thu, Sep 22, 2022, at 13:14, Gavin Ray wrote: >>> >> > Antoine, I can't comment on the Go code (not qualified) but to me, >>> the >>> >> > "verification" test >>> >> > examples look like a mixture between JDBC and Java FlightSQL driver >>> >> usage, >>> >> > and seem solid. >>> >> > >>> >> > There was one reservation I had about the ability to handle >>> datasource >>> >> > namespacing that I brought up early on in the proposal discussions >>> >> > (David responded to it but I got busy and forgot to reply again) >>> >> > >>> >> > If you have a datasource which provides possibly arbitrary levels of >>> >> schema >>> >> > namespace (something like Apache Calcite, for example) >>> >> > How do you represent the table/schema names? >>> >> > >>> >> > Suppose I have a service with a DB layout like this: >>> >> > >>> >> > / foo >>> >> > / bar >>> >> > / baz >>> >> > /qux >>> >> > / table1 >>> >> > - column1 >>> >> > >>> >> > At my dayjob, we have a technology which is very similar to >>> >> > ADBC/FlightSQL >>> >> > (would be great to adopt Substrait + ADBC once they're mature enough) >>> >> > - >>> >> > >>> >> >>> https://github.com/hasura/graphql-engine/blob/master/dc-agents/README.md#data-connectors >>> >> > - >>> >> > >>> >> >>> https://techcrunch.com/2022/06/28/hasura-now-lets-developers-turn-any-data-source-into-a-graphql-api/ >>> >> > >>> >> > We wound up having to redesign the specification to handle >>> datasources >>> >> that >>> >> > don't fit the "database-schema-table" or "database-table" mould >>> >> > >>> >> > In the ADBC schema for schema metadata, it looks like it expects a >>> >> > single >>> >> > "schema" struct: >>> >> > >>> >> >>> https://github.com/apache/arrow-adbc/blob/7866a566f5b7b635267bfb7a87ea49b01dfe89fa/java/core/src/main/java/org/apache/arrow/adbc/core/StandardSchemas.java#L132-L152 >>> >> > >>> >> > If you want to be flexible, IMO it would be good to either: >>> >> > >>> >> > 1. Have DB_SCHEMA_SCHEMA be self-recursive, so that schemas (with or >>> >> > without tables) can be nested arbitrarily deep underneath each other >>> >> > - Fully-Qualified-Table-Name (FQTN) can then be computed by >>> walking >>> >> > up from a table and concating the schema name until the root schema >>> is >>> >> > reached >>> >> > >>> >> > 2. Make "catalog" and "schema" go away entirely, and tables just >>> have a >>> >> > FQTN that is an array, a database is a collection of tables >>> >> > - You can compute what would have been the catalog + schema >>> >> hierarchy >>> >> > by doing a .reduce() over the list of tables and >>> >> > >>> >> > Or maybe there is another, better way. But that's my $0.02 and the >>> only >>> >> > real concern about the API I have, without actually trying to build >>> >> > something with it. >>> >> > >>> >> > >>> >> > >>> >> > >>> >> > >>> >> > On Thu, Sep 22, 2022 at 5:40 AM Antoine Pitrou <anto...@python.org> >>> >> wrote: >>> >> > >>> >> >> >>> >> >> Hello, >>> >> >> >>> >> >> I would urge people to review the proposed ADBC APIs, especially >>> the Go >>> >> >> and Java APIs which probably benefitted from less feedback than the >>> C >>> >> one. >>> >> >> >>> >> >> Regards >>> >> >> >>> >> >> Antoine. >>> >> >> >>> >> >> >>> >> >> Le 21/09/2022 à 17:40, David Li a écrit : >>> >> >> > Hello, >>> >> >> > >>> >> >> > We have been discussing [1] standard interfaces for Arrow-based >>> >> database >>> >> >> access and have been working on implementations of the proposed >>> >> interfaces >>> >> >> [2], all under the name "ADBC". This proposal aims to provide a >>> unified >>> >> >> client abstraction across Arrow-native database protocols (like >>> Flight >>> >> SQL) >>> >> >> and non-Arrow database protocols, which can then be used by Arrow >>> >> projects >>> >> >> like Dataset/Acero and ecosystem projects like Ibis. >>> >> >> > >>> >> >> > For details, see the RFC here: >>> >> >> https://github.com/apache/arrow/pull/14079 >>> >> >> > >>> >> >> > I would like to propose that the Arrow project adopt this RFC, >>> along >>> >> >> with apache/arrow-adbc commit 7866a56 [3], as version 1.0.0 of the >>> ADBC >>> >> API >>> >> >> standard. >>> >> >> > >>> >> >> > Please vote to adopt the specification as described above. (This >>> is >>> >> not >>> >> >> a vote to release any components.) >>> >> >> > >>> >> >> > This vote will be open for at least 72 hours. >>> >> >> > >>> >> >> > [ ] +1 Adopt the ADBC specification >>> >> >> > [ ] 0 >>> >> >> > [ ] -1 Do not adopt the specification because... >>> >> >> > >>> >> >> > Thanks to the DuckDB and R DBI projects for providing feedback on >>> and >>> >> >> implementations of the proposal. >>> >> >> > >>> >> >> > [1]: >>> https://lists.apache.org/thread/cq7t9s5p7dw4vschylhwsfgqwkr5fmf2 >>> >> >> > [2]: https://github.com/apache/arrow-adbc >>> >> >> > [3]: >>> >> >> >>> >> >>> https://github.com/apache/arrow-adbc/commit/7866a566f5b7b635267bfb7a87ea49b01dfe89fa >>> >> >> > >>> >> >> > Thank you, >>> >> >> > David >>> >> >> >>> >> >>> >>
