alamb opened a new issue, #9005: URL: https://github.com/apache/arrow-rs/issues/9005
**Describe the bug** I found this while testing arrow with DataFusion: - https://github.com/apache/datafusion/pull/19355 - Related to https://github.com/apache/arrow-rs/issues/8465 There are several queries like this in the DataFusion tests that work with 57.1.0 but do not work with main (what will be 57.2.0): ```sql CREATE TABLE struct_values ( s1 struct<INT>, s2 struct<a INT,b VARCHAR> ) AS VALUES (struct(1), struct(1, 'string1')), (struct(2), struct(2, 'string2')), (struct(3), struct(3, 'string3')) ; ``` They fail with this error > DataFusion error: Execution error: type mismatch and can't cast to got Struct("c0": Int64, "c1": Utf8) and Struct("a": Int32, "b": Utf8View) **Expected behavior** The tests should pass as they did previously **Additional context** The change came in via 7e637a7559837b5a0171b23469e9652f2f83364b / https://github.com/apache/arrow-rs/pull/8871 from @brancz The tests pass when I revert this commit: ```shell git revert 7e637a7559837b5a0171b23469e9652f2f83364b ``` I believe what is going on is that the `struct` function creates types with placeholder field names (c0, c1, etc). You can see it like this ```sql > select arrow_typeof(struct(1)); +--------------------------------+ | arrow_typeof(struct(Int64(1))) | +--------------------------------+ | Struct("c0": Int64) | +--------------------------------+ 1 row(s) fetched. Elapsed 0.029 seconds. ``` ```sql > select arrow_typeof(struct(1, 'string1')); +------------------------------------------------+ | arrow_typeof(struct(Int64(1),Utf8("string1"))) | +------------------------------------------------+ | Struct("c0": Int64, "c1": Utf8) | +------------------------------------------------+ ``` In prior versions of arrow, the fields could be matched by position, but now they are matched by name and thus the above queries fail. A suggested solution would be to try and match by name first, and if that fails, try and match by position. -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: [email protected] For queries about this service, please contact Infrastructure at: [email protected]
