Grails 2.4 and hibernate4 errors with run-app

Question

I\'ve upgraded an app to Grails 2.4.0, and I\'m using the hibernate4 plugin. When executing run-app the error examples below are generated for each domain class using the in

Answer 1

It's a bug, it seems that you can leave it that way and will cause no problem, but if you don't want to see the message here are some solutions: (Edit: Option 2 seems to work better (see comments in this post))

1.- singleSession configuration from DataSource.groovy

https://jira.grails.org/browse/GRAILS-11198

2.- overriding the H2 dialect:

public class ImprovedH2Dialect extends H2Dialect {
    @Override
    public String getDropSequenceString(String sequenceName) {
        // Adding the "if exists" clause to avoid warnings
        return "drop sequence if exists " + sequenceName;
    }

    @Override
    public boolean dropConstraints() {
        // We don't need to drop constraints before dropping tables, that just
        // leads to error messages about missing tables when we don't have a
        // schema in the database
        return false;
    }
}

Unsuccessful: alter table XXX drop constraint YYY in Hibernate/JPA/HSQLDB standalone