Guillaume VON TOKARSKI ( https://hibernate.atlassian.net/secure/ViewProfile.jspa?accountId=5a9c818... ) *created* an issue Hibernate ORM ( https://hibernate.atlassian.net/browse/HHH?atlOrigin=eyJpIjoiNGQ5MTY1ZDRh... ) / Bug ( https://hibernate.atlassian.net/browse/HHH-16241?atlOrigin=eyJpIjoiNGQ5MT... ) HHH-16241 ( https://hibernate.atlassian.net/browse/HHH-16241?atlOrigin=eyJpIjoiNGQ5MT... ) Unable to use MAX and MIN function on type with AttributeConverter ( https://hibernate.atlassian.net/browse/HHH-16241?atlOrigin=eyJpIjoiNGQ5MT... ) Issue Type: Bug Affects Versions: 6.1.7 Assignee: Unassigned Created: 28/Feb/2023 10:02 AM Priority: Major Reporter: Guillaume VON TOKARSKI ( https://hibernate.atlassian.net/secure/ViewProfile.jspa?accountId=5a9c818... ) The model has java.time.YearMonth attributes being mapped to integers on the DB (MariaDB) Here is how it was used: @Convert(converter = YearMonthConverter.class) @Column(name = "month" , nullable = false ) private YearMonth month; And here is the converter class (based on Jakarta now): public class YearMonthConverter implements AttributeConverter<YearMonth, Integer > { @Override public Integer convertToDatabaseColumn(YearMonth attribute) { return attribute == null ? null : (attribute.getYear() * 100) + attribute.getMonth().getValue(); } @Override public YearMonth convertToEntityAttribute( Integer dbData) { return dbData == null ? null : YearMonth.of(dbData / 100, dbData % 100); } } I’ve got a MAX() query on this column which fails with the following error: org.hibernate.QueryException: Parameter 1 of function max() has type COMPARABLE, but argument is of type java.time.YearMonth It’s worth noticing that the ORM is able to read/write this column from the DB, it only fails to run functions like MIN or MAX. The debugging took me to a section of the code in ArgumentTypesValidator where the code considers that the node type YearMonth is incompatible with the FunctionParameterType COMPARABLE. Let me know if there is anything else that I can provide. ( https://hibernate.atlassian.net/browse/HHH-16241#add-comment?atlOrigin=ey... ) Add Comment ( https://hibernate.atlassian.net/browse/HHH-16241#add-comment?atlOrigin=ey... ) Get Jira notifications on your phone! Download the Jira Cloud app for Android ( https://play.google.com/store/apps/details?id=com.atlassian.android.jira.... ) or iOS ( https://itunes.apple.com/app/apple-store/id1006972087?pt=696495&ct=Em... ) This message was sent by Atlassian Jira (v1001.0.0-SNAPSHOT#100217- sha1:65be9f2 )