All,

I have a non-hibernate application that I'm trying to port to hibernate 3.0. Currently, the non-hibernate application does things like this:

update clientTable set lastHeartBeat=sysdate where id=35;

In the above example, "sysdate" is particular to Oracle and represents the current time. I like using the system time because we are running in a clustered environment and our application servers could conceivably have different times on them - hence we use the databases's time. Doing it this way, I also don't need to READ the sysdate from the DB *before* making the above call.

I'd be interested to know if I could do something like this in hibernate?

Thanks,

-john

You could use triggers, but the timestamp datatype would be better. If you change the type of you column to timestamp (I presume it's datetime at the moment) then Oracle will update it automatically whenever you update the row, whether you use hibernate or not. Hibernate has full support for the timestamp SQL type: just map the property with insert="false" update="false" to ensure that the value is only ever updated by the server (timestamp columns may be overwritten by user-provided values).

this doesn't work for me. are you getting confused with the MySql timestamp type ?

I'm not getting confused with MySQL, as I've never used that. However it might be that timestamp on SQLServer is different from timestamp on whatever DBMS you're using.

Note that I mean the SQL column type should be timestamp: setting the column type to timestamp in your mapping isn't enough, you must do it in the DB.

well, i'm using Oracle as discussed in the original post and i have set the db column to timestamp using the sql-type attribute of <column> and it is the right type in the db but i can't get Oracle to update that column automatically. i just thought i might be missing a trick here.

maybe the <sql-update> element might another way to achieve the required functionality though there is an argument that it defeats the purpose of using an ORM.

You could read up on the <version> tag, maybe it'll do what you need?