orm

问题 What if I have some model, with non-default features (like soft delete or custom id name) and want to create a Migration file from it, which would have all these properties in it? So here is my model: class Test extends Model { use SoftDeletes; protected $primaryKey = 'test_id'; protected $table = 'my_flights'; protected $dates = ['deleted_at']; } And I want my Migration file to be based on it. But when I use command php artisan make:migration create_test(s)_table (I tried both test and tests

问题 In spring batch reference, there is a pattern called driving query pattern https://docs.spring.io/spring-batch/4.1.x/reference/html/common-patterns.html#drivingQueryBasedItemReaders I don't know if I misunderstand this pattern right, doesn't driving query pattern cause N+1 problem? It looks like a classic N+1 problem to me, especially they are bad practice in ORM world. 回答1: Yes it does. For each item, the processor will issue another query to grab additional information about the current

问题 I have a belongsToMany relationship between two tables which is configured using a through table. class UsersTable extends Table { public function initialize(array $config) { $this->belongsToMany('Groups', [ 'through' => 'GroupsUsers', ]); } } class GroupsTable extends Table { public function initialize(array $config) { $this->belongsToMany('Users', [ 'through' => 'GroupsUsers', ]); } } class GroupsUsersTable extends Table { public function initialize(array $config) { $this->belongsTo('Groups

问题 I have a belongsToMany relationship between two tables which is configured using a through table. class UsersTable extends Table { public function initialize(array $config) { $this->belongsToMany('Groups', [ 'through' => 'GroupsUsers', ]); } } class GroupsTable extends Table { public function initialize(array $config) { $this->belongsToMany('Users', [ 'through' => 'GroupsUsers', ]); } } class GroupsUsersTable extends Table { public function initialize(array $config) { $this->belongsTo('Groups

问题 I have written a RestController in my SpringBoot app. I am using a MongoDB as well. This is my entity: public class LocationEntity { @Id private String id; private String name; @DBRef(lazy = true) @JsonIgnore private UserEntity owner; private String description; @DBRef(lazy = true) private List<RoleEntity> roles; private Date date; public LocationEntity(String name, UserEntity owner, String description, List<RoleEntity> roles, Date date) { this.name = name; this.owner = owner; this

问题 I'm trying to use schema_translate_map to change a schema: Base = declarative_base() class DataAccessLayer(): def __init__(self): conn_string = "mysql+mysqlconnector://root:root@localhost/" self.engine = create_engine(conn_string) Session = sessionmaker() Session.configure(bind=self.engine) self.session = Session() def change_schema(self): self.session.connection(execution_options={"schema_translate_map": {"belgarath": "belgarath_test"}}) class Player(Base): __tablename__ = "player" __table

问题 I'm trying to use schema_translate_map to change a schema: Base = declarative_base() class DataAccessLayer(): def __init__(self): conn_string = "mysql+mysqlconnector://root:root@localhost/" self.engine = create_engine(conn_string) Session = sessionmaker() Session.configure(bind=self.engine) self.session = Session() def change_schema(self): self.session.connection(execution_options={"schema_translate_map": {"belgarath": "belgarath_test"}}) class Player(Base): __tablename__ = "player" __table

问题 I'm using Django 3.0 + MariaDB. I've created a models.py from an existent database with the "python manage.py inspectdb > models.py" command. I need now to set the options for the Foreign Keys. As you know in a database you can have multiple options for the Foreign Keys: the first classic is "ON_DELETE" and the second is 'ON_UPDATE' (You can even have more options in PostgreSQL). In Django, there is just an "on_delete", but no "on_update" option, what I found very surprising. I found nothing

问题 I'm using Django 3.0 + MariaDB. I've created a models.py from an existent database with the "python manage.py inspectdb > models.py" command. I need now to set the options for the Foreign Keys. As you know in a database you can have multiple options for the Foreign Keys: the first classic is "ON_DELETE" and the second is 'ON_UPDATE' (You can even have more options in PostgreSQL). In Django, there is just an "on_delete", but no "on_update" option, what I found very surprising. I found nothing

问题 i have a problem with doctrine and i getting this error from auto generated entity file "Class "Users" is not a valid entity or mapped super class.". File and comments inside looks like fine i dont understund why or i something miss? Some piece of code <?php use Doctrine\ORM\Mapping as ORM; /** * Users * * @ORM\Table(name="users", uniqueConstraints={@ORM\UniqueConstraint(name="username", columns={"username"})}) * @ORM\Entity */ class Users { /** * @var integer * * @ORM\Column(name="userid",