Omega359 opened a new issue, #15236: URL: https://github.com/apache/datafusion/issues/15236
### Describe the bug union by name seems to not be working as expected: ```sql > create table t1 (x varchar(255), y varchar(255), z varchar(255)); 0 row(s) fetched. Elapsed 0.005 seconds. > insert into t1 values ('a', 'b', 'c'); +-------+ | count | +-------+ | 1 | +-------+ 1 row(s) fetched. Elapsed 0.004 seconds. > select t1.x, t1.y, t1.z from t1 union by name select t1.z, t1.y, t1.x, 'd' as zz from t1; +---+---+---+------+ | x | y | z | zz | +---+---+---+------+ | c | b | a | d | | a | b | c | NULL | +---+---+---+------+ 2 row(s) fetched. Elapsed 0.011 seconds. > select x, y, z from t1 union all by name select z, y, x, 'd' as zz from t1; +---+---+---+------+ | x | y | z | zz | +---+---+---+------+ | a | b | c | NULL | | c | b | a | d | +---+---+---+------+ 2 row(s) fetched. Elapsed 0.007 seconds. ``` The same result if using 2 tables: ```sql > create table t2 (x varchar(255), y varchar(255), z varchar(255)); 0 row(s) fetched. Elapsed 0.004 seconds. > insert into t2 values ('a', 'b', 'c'); +-------+ | count | +-------+ | 1 | +-------+ 1 row(s) fetched. Elapsed 0.003 seconds. > select x, y, z from t1 union all by name select z, y, x, 'd' as zz from t2; +---+---+---+------+ | x | y | z | zz | +---+---+---+------+ | a | b | c | NULL | | c | b | a | d | +---+---+---+------+ 2 row(s) fetched. Elapsed 0.007 seconds. > select x, y, z from t1 union all by name select z, y, x from t2; +---+---+---+ | x | y | z | +---+---+---+ | a | b | c | | c | b | a | +---+---+---+ 2 row(s) fetched. Elapsed 0.005 seconds. > select x, y, z from t1 union all by name select z, y, x from t2 order by x; +---+---+---+ | x | y | z | +---+---+---+ | a | b | c | | c | b | a | +---+---+---+ 2 row(s) fetched. Elapsed 0.007 seconds. ``` ### To Reproduce See sql above. ### Expected behavior _No response_ ### Additional context _No response_ -- 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: github-unsubscr...@datafusion.apache.org.apache.org For queries about this service, please contact Infrastructure at: us...@infra.apache.org --------------------------------------------------------------------- To unsubscribe, e-mail: github-unsubscr...@datafusion.apache.org For additional commands, e-mail: github-h...@datafusion.apache.org