JPQL #ManyToMany querying - mysql

Question

I need to write two different yet similar JPQL queries and currently lack the expertise. I really hope one can help.
Return all items associated with one or more tags, by querying the current Tag class and returning the collection of items?
Return all items that holds a reference to the current Tag class, by querying over every item and comparing with the collection of tags?
Additional questions:
When i add a tag to the collection of an item, do the item automatically get added to the collection in the tag?
Any ideas on how i can sort the returned items depending on the number of tags they match? Can i include this in the JPQL query?
Would it be better for my Tag class to have the String keyword as #id?
My code:
#Entity
#NamedQueries({
#NamedQuery(name = Item.FIND_ALL, query = "select i from Item i")
})
#TableGenerator(name = "Item_ID_Generator", table = "ITEM_ID_GEN", pkColumnName = "PRIMARY_KEY_NAME",
pkColumnValue = "Item.id", valueColumnName = "NEXT_ID_VALUE")
public class Item implements Serializable {
public static final String FIND_ALL = "Item.findAll";
// private static final long serialVersionUID = 1L;
#Id
#Column(nullable = false)
#GeneratedValue(strategy = GenerationType.TABLE, generator = "Item_ID_Generator")
private Integer id;
#ManyToMany(fetch = FetchType.LAZY, cascade = {CascadeType.PERSIST, CascadeType.REMOVE})
#JoinTable(name = "jnd_item_tag",
joinColumns = #JoinColumn(name = "item_fk"),
inverseJoinColumns = #JoinColumn(name = "tag_fk"))
private List<Tag> tags = new ArrayList();
}
#Entity
public class Tag implements Serializable {
private static final long serialVersionUID = 1L;
#Id
#Column(nullable = false)
#GeneratedValue(strategy = GenerationType.AUTO)
private Integer id;
#Column(unique = true)
private String keyword;
#ManyToMany(mappedBy = "tags")
private List<Item> referencedByItem;
}

Answer 1

Execute the following query, which will return the matched tags sets, and the matched tags:
SELECT i, t FROM Item i JOIN i.tags t WHERE t.keyword IN :listOfTags
I this case can be this way:
#NamedQuery(name = "selectByTags", query = "SELECT i, t FROM Item i JOIN i.tags t WHERE t.keyword IN :listOfTags")
//and here you need set your list
List<Tag> tags = daoTags.getListTags();
query.setParameter("listOfTags", listOfTags);
I think that adapting this query solves both requests for your question.