PHP Phalcon. Use postgres nextval(sequence) in model - php

Question

I have a table in Postgres with DDL like this one:
CREATE TABLE robots(
robot_id INTEGER NOT NULL CONSTRAINT robot_id_pkey PRIMARY KEY,
name TEXT
);
I know I can insert a record with following SQL statement:
INSERT INTO robots (robot_id, name) VALUES (nextval('robots_seq'), 'WALL-E');
I need to make CRUD operations in Phalcon for this table. Also I want to use ORM features.
So I do:
$robot = new Robots();
$robot->setRobotId(new \Phalcon\Db\RawValue("nextval('robots_seq')"));
$robot->setName('WALL-E');
$robot->save();
And get the following exception:
Uncaught PDOException: SQLSTATE[22P02]: Invalid text representation:
7 ERROR: invalid input syntax for integer: 'nextval('robots_seq')';
Is there any way to accomplish this ?

Answer 1

To tell Phalcon what is name of your model sequence use function getSequenceName:
public function getSequenceName() {
return 'category_id_seq';
}

Answer 2

Phalcon assumes that your models with serial (auto increment) columns will have a sequence named [table_name]_[column_name]_seq.
In your case, in order to make Phalcon take care of handling auto increment columns you should have a sequence named robots_robot_id_seq instead of robots_seq for the column robot_id (which I'd call just "id", by the way).
This way you do not have to worry about setting the id when creating an object and after saving Phalcon will fill that field automatically for you:
CREATE TABLE robots(
robot_id SERIAL PRIMARY KEY NOT NULL,
name TEXT
);
$robot = new Robots();
$robot->setName('WALL-E');
$robot->save();
$robot->getRobotId(); // Should return last "nextval()" sequence
Hope it helps.