Activity record of data source schema mode _php tutorial

"Intent of the activity record"

An object that wraps a row in a data table or view, encapsulates the database access, and adds domain logic to the data.

"Applicable Scenarios for Activity records"

Applies to less complex domain logic, such as CRUD operations.

"Operating mechanism of activity records"

objects have both data and behavior. It uses the most straightforward method of placing data access logic in a domain object.

The essence of an activity record is a domain model in which the records structure in the class and base database in the domain model should match exactly, and each field of the class corresponds to each column of the table.

In general, the activity record includes the following methods:

1, the data row constructs an activity record instance;

2, for the future of the insertion of the table to construct a new instance;

3, using static search method to wrap the common SQL query and return activity records;

4. Update the database and insert the data from the activity record into the database;

5, get or set the domain;

6. Realize part of business logic.

"Advantages and disadvantages of activity logging"

Advantages:

1, simple, easy to create and easy to understand.

2. Reduce code replication when using transactional scripting.

3, you can change the database structure without changing the domain logic.

4. Derivation and test validation based on a single activity record can be effective.

Disadvantages:

1. There is no hidden relational database.

2. The activity record is valid only if the active Record object corresponds directly to the table in the database.

3, the requirements of the design of the object and the design of the database tightly coupled, which makes it difficult to further reconstruct the project

"Activity records and other modes"

Data source schema mode row data entry: The activity record is very similar to the row data entry. The main difference between the two is that the row data portal has only database access and the active record has both the data source logic and the domain logic.

"PHP Example of activity log"

 
 

  
  

  
 
  
  

  
 
  
  

  
/** 
  
  

  
* Enterprise Application Architecture Data source schema mode of activity record 2010-10-17 sz
  
  

  
* @author phppan.p#gmail.com http://www.phppan.com
  
  

  
* Members of the Brother Society (http://www.blog-brother.com/)
  
  

  
* @package Architecture
  
  

  
 */  
  
  

  
 
  
  

  
/** 
  
  

  
* Order Class
  
  

  
 */  
  
  

  
class Order {
  
  

  
 
  
  

  
 /** 
  
  

  
* Order ID
  
  

  
* @var   
  
  

  
 */  
  
  

  
 Private   $_order_id; 
  
  

  
 
  
  

  
 /** 
  
  

  
* Customer ID
  
  

  
* @var   
  
  

  
 */  
  
  

  
 Private   $_customer_id; 
  
  

  
 
  
  

  
 /** 
  
  

  
* Order Amount
  
  

  
* @var   
  
  

  
 */  
  
  

  
 Private   $_amount; 
  
  

  
 
  
  

  
  Public   function  __construct ($order _id,  $customer _id, $amount ) { 
  
  

  
 $this ->_order_id = $order _id ; 
  
  

  
 $this ->_customer_id = $customer _id ; 
  
  

  
 $this ->_amount = $amount ; 
  
  

  
}
  
  

  
 
  
  

  
 /** 
  
  

  
* Delete operations for instances
  
  

  
 */  
  
  

  
  Public    function  delete() {
  
  

  
 $sql  =  "DELETE from Order SET WHERE order_id ="  .  $this ->_order_id. "and customer_id ="  .  $this ->_customer_id; 
  
  

  
 return db::query ($sql); 
  
  

  
}
  
  

  
 
  
  

  
 /** 
  
  

  
* Update operation of the instance
  
  

  
 */  
  
  

  
  Public   function  Update () {
  
  

  
}
  
  

  
 
  
  

  
 /** 
  
  

  
* Insert Operation
  
  

  
 */  
  
  

  
  Public    http://www.bkjia.com/PHPjc/486087.htmlwww.bkjia.comtrue/http www.bkjia.com/PHPjc/486087.htmltecharticleAn object that wraps a row in a data table or view, encapsulates the database access, and adds domain logic to the data. "The applicable field of the activity record ...

  
  

  
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