php day-10 instantiation of data tables and classes

1.Instantiate an operation class of a database table

$user=new Model("User"); (Equivalent M method)

//"User" It is database table name. If there is a prefix, there is no need to add it. You can also write it like this

$list=$user->select();

var_dump($list);

2. When instantiating a database table, instantiate a custom model class at the same time, such as:
$user=new Model( "User","CommonModel");//CommonModel is a custom model class in the lib/model directory.
$list=$user->select();
var_dump($list);
$user->test();//The test method is a method defined in the custom model class CommonModel. Generally used as public models in this manner.

3.

Instantiate a custom model class: (D method?)

$user=new UserModel ();//No need to pass The parameter table, because the model itself has given parameters, is user. This method is generally used when it is used as a single model function.

4.

Instantiate an empty database operation class for use in detailed database operation statements.

$user=new Model();

$list1=$user->query("select * from db_user");//If the database table has a prefix, A prefix must be added here, such as the db prefix here.

$list2=$user->query("select * from db_id");

var_dump($list1);

var_dump( $list2);

The above introduces the instantiation of php day-10 data tables and classes, including aspects of the content. I hope it will be helpful to friends who are interested in PHP tutorials.