How to add multiple named parameters to the SQL statement?
I would like to write something like this in myBatis (using anotations instead of XML):
@Insert("INSERT INTO friendships (user_id, friend_id) VALUES (#{user.id}, {friend.id})")
public void insert(User user, User friend);
Is this possible? How exactly?
(Note, I would like to use Objects of type User for type-safty. I know that using int parameters and use #{1} and #{2} as plac开发者_JS百科eholders would work)
You can use annotations to provide a namespace for multiple input parameters. These essentially give nice names to the #{1.foo} and #{2.bar} identifiers.
@Insert("INSERT INTO friendships (user_id, friend_id) VALUES (#{user.id},
#{friend.id})")
public void insert(@Param(value="user") User user, @Param(value="friend") User friend)
It seems like this is not possible, so I created a wrapper class:
class Friendship {
private final User user;
private final User friend;
public Friendship(User user, User friend) {
this.user = user;
this.friend = friend;
}
public int getUserId(){
return user.getId();
}
public int getFriendId(){
return friend.getId();
}
}
And changed the Mapper to this:
@Insert("INSERT INTO friendships (user_id, friend_id) VALUES (#{userId}, #{friendId})")
public void insert(Friendship friendship);
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