@ManyToMany(cascade={CascadeType.PERSIST,CascadeType.MERGE})
@JoinTable(name = "adgroup_ad", joinColumns = { @JoinColumn(name = "adgroup_id") }, inverseJoinColumns = { @JoinColumn(name = "ad_version_id") })
@ManyToMany(cascade={CascadeType.PERSIST,CascadeType.MERGE})
@JoinTable(name = "adgroup_ad", joinColumns = { @JoinColumn(name = "adgroup_id") }, inverseJoinColumns = { @JoinColumn(name = "ad_version_id") })