[ https://issues.apache.org/jira/browse/SPARK-47210?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]
Mihailo Milosevic updated SPARK-47210: -------------------------------------- Summary: Addition of implicit casting without indeterminate support (was: Implicit casting on collated expressions) > Addition of implicit casting without indeterminate support > ---------------------------------------------------------- > > Key: SPARK-47210 > URL: https://issues.apache.org/jira/browse/SPARK-47210 > Project: Spark > Issue Type: Sub-task > Components: SQL > Affects Versions: 4.0.0 > Reporter: Mihailo Milosevic > Priority: Major > Labels: pull-request-available > > *What changes were proposed in this pull request?* > This PR adds automatic casting and collations resolution as per `PGSQL` > behaviour: > 1. Collations set on the metadata level are implicit > 2. Collations set using the `COLLATE` expression are explicit > 3. When there is a combination of expressions of multiple collations the > output will be: > - if there are explicit collations and all of them are equal then that > collation will be the output > - if there are multiple different explicit collations > `COLLATION_MISMATCH.EXPLICIT` will be thrown > - if there are no explicit collations and only a single type of non default > collation, that one will be used > - if there are no explicit collations and multiple non-default implicit ones > `COLLATION_MISMATCH.IMPLICIT` will be thrown > Another thing is that `INDETERMINATE_COLLATION` should only be thrown on > comparison operations, and we should be able to combine different implicit > collations for certain operations like concat and possible others in the > future. > This is why I had to add another predefined collation id named > `INDETERMINATE_COLLATION_ID` which means that the result is a combination of > conflicting non-default implicit collations. Right now it has an id of -1 so > it fails if it ever goes to the `CollatorFactory`. > *Why are the changes needed?* > We need to be able to compare columns and values with different collations > and set a way of explicitly changing the collation we want to use. -- This message was sent by Atlassian Jira (v8.20.10#820010) --------------------------------------------------------------------- To unsubscribe, e-mail: issues-unsubscr...@spark.apache.org For additional commands, e-mail: issues-h...@spark.apache.org