Custom H2 Hibernate Dialect to support differences in MySQL and H2 query syntax

H2MysqlSupportDialect.groovy

import org.hibernate.dialect.H2Dialect
import org.hibernate.dialect.function.SQLFunctionTemplate
import org.hibernate.type.StandardBasicTypes

class H2MysqlSupportDialect extends H2Dialect {

    H2MysqlSupportDialect() {
        registerFunction('datediff', new SQLFunctionTemplate(StandardBasicTypes.DATE, "datediff('DAY', ?2, ?1)"))
    }
}