Register Register Member Login Member Login Member Login Forgot Password ??
PHP , ASP , ASP.NET, VB.NET, C#, Java , jQuery , Android , iOS , Windows Phone
 

Registered : 109,036

HOME > PHP Manual > One-table examples





ลองใช้ค้นหาข้อมูล


   
Bookmark.

One-table examples

The following set of examples all use the Relational DAS to work with a data graph containing just one application data object, a single company and the data just to be found the company table. These examples do not exercise the power of SDO or the Relational DAS and of course the same result could be achieved more economically with direct SQL statements but they are intended to illustrate how to work with the Relational DAS.

For this very simple scenario it would be possible to simplify the database metadata to include just the company table - if that were done the second and third arguments to the constructor and the column specifier used in the query example would become optional.

Example #1 Creating a data object

The simplest example is that of creating a single data object and writing it to the database. In this example a single company object is created, its name is set to 'Acme', and the Relational DAS is called to write the changes to the database. The company name is set here using the property name method. See the Examples section on the SDO extension for other ways of accessing the properties of an object.

Data objects can only be created when you have a data object to start with, however. It is for that reason that the first call to the Relational DAS here is to obtain a root object. This is in effect how to ask for an empty data graph - the special root object is the true root of the tree. The company data object is then created with a call to createDataObject() on the root object. This creates the company data object and inserts it in the graph by inserting into a multi-valued containment property on the root object called 'company'.

When the Relational DAS is called to apply the changes a simple insert statement 'INSERT INTO company (name) VALUES ("Acme");' will be constructed and executed. The auto-generated primary key will be set into the data object and the change summary will be reset, so that it would be possible to continue working with the same data object, modify it, and apply the newer changes a second time.

<?php
require_once 'SDO/DAS/Relational.php';
require_once 
'company_metadata.inc.php';

/**************************************************************
* Construct the DAS with the metadata
***************************************************************/
$das = new SDO_DAS_Relational ($database_metadata,'company',$SDO_containment_metadata);

/**************************************************************
* Obtain a root object and create a company object underneath.
* Make a simple change to the data object. 
***************************************************************/
$root $das  -> createRootDataObject();
$acme $root -> createDataObject('company');

$acme->name "Acme";

/**************************************************************
* Get a database connection and write the object to the database
***************************************************************/
$dbh = new PDO(PDO_DSN,DATABASE_USER,DATABASE_PASSWORD);
$das -> applyChanges($dbh$root);
?>

Example #2 Retrieving a data object

In this example a single data object is retrieved from the database - or possibly more than one if there is more than one company called 'Acme'. For each company returned, the name and id properties are echoed.

In this example the third argument to executeQuery(), the column specifier is needed as there are other tables in the metadata with column names of name and id. If there were no possible ambiguity it could be omitted.

<?php
require_once 'SDO/DAS/Relational.php';
require_once 
'company_metadata.inc.php';

/**************************************************************
* Construct the DAS with the metadata
***************************************************************/
$das = new SDO_DAS_Relational ($database_metadata,'company',$SDO_containment_metadata);

/**************************************************************
* Get a database connection
***************************************************************/
$dbh = new PDO(PDO_DSN,DATABASE_USER,DATABASE_PASSWORD);

/**************************************************************
* Issue a query to obtain a company object - possibly more if they exist
***************************************************************/
$root $das->executeQuery($dbh,
         
'select name, id from company where name="Acme"',
          array(
'company.name''company.id') );

/**************************************************************
* Echo name and id 
***************************************************************/
foreach ($root['company'] as $company) {
  echo 
"Company obtained from the database has name = " 
  
$company['name'] . " and id " $company['id'] . "\n";
}
?>

Example #3 Updating a data object

This example combines the previous two, in the sense that in order to be updated the object must first be retrieved. The application code reverses the company name (so 'Acme' becomes 'emcA') and then the changes are written back to the database in the same way that they were when the object was created. Because the query searches for the name both ways round the program can be run repeatedly to find the company and reverse its name each time.

In this example the same instance of the Relational DAS is reused for the applyChanges(), as is the PDO database handle. This is quite alright; it also alright to allow the previous instances to be garbage collected and to obtain new instances. No state data regarding the graph is held the Relational DAS once it has returned a data graph to the application. All necessary data is either within the graph itself, or can be reconstructed from the metadata.

<?php
require_once 'SDO/DAS/Relational.php';
require_once 
'company_metadata.inc.php';

/**************************************************************
* Construct the DAS with the metadata
***************************************************************/
$das = new SDO_DAS_Relational ($database_metadata,'company',$SDO_containment_metadata);

/**************************************************************
* Get a database connection
***************************************************************/
$dbh = new PDO(PDO_DSN,DATABASE_USER,DATABASE_PASSWORD);

/**************************************************************
* Issue a query to obtain a company object - possibly more if they exist
***************************************************************/
$root $das->executeQuery($dbh,
  
'select name, id from company where name="Acme" or name="emcA"',
  array(
'company.name''company.id') );

/**************************************************************
* Alter the name of just the first company
***************************************************************/
$company $root['company'][0];
echo 
"obtained a company with name of " $company->name "\n";
$company->name strrev($company->name);

/**************************************************************
* Write the change back
***************************************************************/
$das->applyChanges($dbh,$root);
?>

Example #4 Deleting a data object

Any companies called 'Acme' or its reverse 'emcA' are retrieved. They are then all deleted from the graph with unset.

In this example they are all deleted in one go by unsetting the containing property (the property defining the containment relationship). It is also possible to delete them individually.

<?php
require_once 'SDO/DAS/Relational.php';
require_once 
'company_metadata.inc.php';

/**************************************************************
* Construct the DAS with the metadata
***************************************************************/
$das = new SDO_DAS_Relational ($database_metadata,'company',$SDO_containment_metadata);

/**************************************************************
* Get a database connection
***************************************************************/
$dbh = new PDO(PDO_DSN,DATABASE_USER,DATABASE_PASSWORD);

/**************************************************************
* Issue a query to obtain a company object - possibly more if they exist
***************************************************************/
$root $das->executeQuery($dbh,
  
'select name, id from company where name="Acme" or name="emcA"',
  array(
'company.name''company.id') );

/**************************************************************
* Delete any companies found from the data graph
***************************************************************/
unset($root['company']);

/**************************************************************
* Write the change(s) back
***************************************************************/
$das->applyChanges($dbh,$root);
?>



ThaiCreate.Com Forum


Comunity Forum Free Web Script
Jobs Freelance Free Uploads
Free Web Hosting Free Tools

สอน PHP ผ่าน Youtube ฟรี
สอน Android การเขียนโปรแกรม Android
สอน Windows Phone การเขียนโปรแกรม Windows Phone 7 และ 8
สอน iOS การเขียนโปรแกรม iPhone, iPad
สอน Java การเขียนโปรแกรม ภาษา Java
สอน Java GUI การเขียนโปรแกรม ภาษา Java GUI
สอน JSP การเขียนโปรแกรม ภาษา Java
สอน jQuery การเขียนโปรแกรม ภาษา jQuery
สอน .Net การเขียนโปรแกรม ภาษา .Net
Free Tutorial
สอน Google Maps Api
สอน Windows Service
สอน Entity Framework
สอน Android
สอน Java เขียน Java
Java GUI Swing
สอน JSP (Web App)
iOS (iPhone,iPad)
Windows Phone
Windows Azure
Windows Store
Laravel Framework
Yii PHP Framework
สอน jQuery
สอน jQuery กับ Ajax
สอน PHP OOP (Vdo)
Ajax Tutorials
SQL Tutorials
สอน SQL (Part 2)
JavaScript Tutorial
Javascript Tips
VBScript Tutorial
VBScript Validation
Microsoft Access
MySQL Tutorials
-- Stored Procedure
MariaDB Database
SQL Server Tutorial
SQL Server 2005
SQL Server 2008
SQL Server 2012
-- Stored Procedure
Oracle Database
-- Stored Procedure
SVN (Subversion)
แนวทางการทำ SEO
ปรับแต่งเว็บให้โหลดเร็ว


Hit Link
   







Load balance : Server 02
ThaiCreate.Com Logo
© www.ThaiCreate.Com. 2003-2024 All Rights Reserved.
ไทยครีเอทบริการ จัดทำดูแลแก้ไข Web Application ทุกรูปแบบ (PHP, .Net Application, VB.Net, C#)
[Conditions Privacy Statement] ติดต่อโฆษณา 081-987-6107 อัตราราคา คลิกที่นี่