Setting a JPA timestamp column to be generated by the database?

I fixed the issue by changing the code to

@Basic(optional = false)
@Column(name = "LastTouched", insertable = false, updatable = false)
@Temporal(TemporalType.TIMESTAMP)
private Date lastTouched;

So the timestamp column is ignored when generating SQL inserts. Not sure if this is the best way to go about this. Feedback is welcome.

I realize this is a bit late, but I've had success with annotating a timestamp column with

@Column(name="timestamp", columnDefinition="TIMESTAMP DEFAULT CURRENT_TIMESTAMP")

This should also work with CURRENT_DATE and CURRENT_TIME. I'm using JPA/Hibernate with Oracle, so YMMV.

@Column(nullable = false, updatable = false)
@CreationTimestamp
private Date created_at;

this worked for me. more info