Implement batch insert of models (multiline insert)

[eugeneRover]

It would be great if multiple models can be saved in one SQL INSERT.
Batch operation (that already exists in JavaLite) does not provide required functionality (it uses the same single-line INSERT instead).
Example:

class User extends Model {
      public User(String name, Integer age){
           set("name", prodItem, "age", age);
      }
}

...

User c1 = new User("a", 4); 
User c2 = new User("b", 5); 
User c3 = new User("c", 6); 

// suggested method, it executes following SQL INSERT with appropriate query parameters set: 
// INSERT INTO users(name, age) VALUES (?,?), (?,?), (?,?) RETURNING id
User.saveMultiple(List.of(c1,c2,c3));

// after the operation, all input models are saved, and have ID set
assert(c1.getId() != null);
assert(c2.getId() != null);
assert(c3.getId() != null);

[ipolevoy]

@eugeneRover the batch operations you are mentioning will do what you need, except setting the IDs on the models. Is there anything else missing?

[eugeneRover]

Batch operation generate single-row INSERTs, for my example it will be 3 SQL calls:

INSERT INTO users(name, age) VALUES (?,?) RETURNING id
INSERT INTO users(name, age) VALUES (?,?) RETURNING id
INSERT INTO users(name, age) VALUES (?,?) RETURNING id

What I propose is to create multi-row INSERT , like this:

INSERT INTO users(name, age) VALUES (?,?), (?,?), (?,?) RETURNING id

This will give us drastic speed boost on massive INSERT operations.