sdo.das.rel.examples.one-table.html
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<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"><html> <head> <title>One-table examples</title> <meta http-equiv="content-type" content="text/html; charset=UTF-8"> </head> <body><div style="text-align: center;"> <div class="prev" style="text-align: left; float: left;"><a href="sdo.das.rel.metadata.html">Specifying the metadata</a></div> <div class="next" style="text-align: right; float: right;"><a href="sdo.das.rel.examples.two-table.html">Two-table examples</a></div> <div class="up"><a href="sdo.das.rel.examples.html">Examples</a></div> <div class="home"><a href="index.html">PHP Manual</a></div></div><hr /><div id="sdo.das.rel.examples.one-table" class="section"> <h2 class="title">One-table examples</h2> <p class="para"> 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. </p> <p class="para"> 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. </p> <p class="para"> <div class="example"> <p><b>Example #1 Creating a data object</b></p> <div class="example-contents"><p> 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 <a href="sdo.examples.html" class="link">Examples</a> section on the SDO extension for other ways of accessing the properties of an object. </p></div> <div class="example-contents"><p> 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 <b>createDataObject()</b> 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'. </p></div> <div class="example-contents"><p> 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. </p></div> <div class="example-contents"><div class="phpcode"><code><span style="color: #000000"><span style="color: #0000BB"><?php<br /></span><span style="color: #007700">require_once </span><span style="color: #DD0000">'SDO/DAS/Relational.php'</span><span style="color: #007700">;<br />require_once </span><span style="color: #DD0000">'company_metadata.inc.php'</span><span style="color: #007700">;<br /><br /></span><span style="color: #FF8000">/**************************************************************<br />* Construct the DAS with the metadata<br />***************************************************************/<br /></span><span style="color: #0000BB">$das </span><span style="color: #007700">= new </span><span style="color: #0000BB">SDO_DAS_Relational </span><span style="color: #007700">(</span><span style="color: #0000BB">$database_metadata</span><span style="color: #007700">,</span><span style="color: #DD0000">'company'</span><span style="color: #007700">,</span><span style="color: #0000BB">$SDO_containment_metadata</span><span style="color: #007700">);<br /><br /></span><span style="color: #FF8000">/**************************************************************<br />* Obtain a root object and create a company object underneath.<br />* Make a simple change to the data object. <br />***************************************************************/<br /></span><span style="color: #0000BB">$root </span><span style="color: #007700">= </span><span style="color: #0000BB">$das </span><span style="color: #007700">-> </span><span style="color: #0000BB">createRootDataObject</span><span style="color: #007700">();<br /></span><span style="color: #0000BB">$acme </span><span style="color: #007700">= </span><span style="color: #0000BB">$root </span><span style="color: #007700">-> </span><span style="color: #0000BB">createDataObject</span><span style="color: #007700">(</span><span style="color: #DD0000">'company'</span><span style="color: #007700">);<br /><br /></span><span style="color: #0000BB">$acme</span><span style="color: #007700">-></span><span style="color: #0000BB">name </span><span style="color: #007700">= </span><span style="color: #DD0000">"Acme"</span><span style="color: #007700">;<br /><br /></span><span style="color: #FF8000">/**************************************************************<br />* Get a database connection and write the object to the database<br />***************************************************************/<br /></span><span style="color: #0000BB">$dbh </span><span style="color: #007700">= new </span><span style="color: #0000BB">PDO</span><span style="color: #007700">(</span><span style="color: #0000BB">PDO_DSN</span><span style="color: #007700">,</span><span style="color: #0000BB">DATABASE_USER</span><span style="color: #007700">,</span><span style="color: #0000BB">DATABASE_PASSWORD</span><span style="color: #007700">);<br /></span><span style="color: #0000BB">$das </span><span style="color: #007700">-> </span><span style="color: #0000BB">applyChanges</span><span style="color: #007700">(</span><span style="color: #0000BB">$dbh</span><span style="color: #007700">, </span><span style="color: #0000BB">$root</span><span style="color: #007700">);<br /></span><span style="color: #0000BB">?></span></span></code></div> </div> </div> </p> <p class="para"> <div class="example"> <p><b>Example #2 Retrieving a data object</b></p> <div class="example-contents"><p> 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 <var class="varname">name</var> and <var class="varname">id</var>⌨️ 快捷键说明
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