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Diffstat (limited to 'demos/quickstart/protected/pages/Database/SqlMap.page')
| -rw-r--r-- | demos/quickstart/protected/pages/Database/SqlMap.page | 84 |
1 files changed, 42 insertions, 42 deletions
diff --git a/demos/quickstart/protected/pages/Database/SqlMap.page b/demos/quickstart/protected/pages/Database/SqlMap.page index 4b462168..bac1ba44 100644 --- a/demos/quickstart/protected/pages/Database/SqlMap.page +++ b/demos/quickstart/protected/pages/Database/SqlMap.page @@ -1,8 +1,8 @@ <com:TContent ID="body"> <!-- $Id $ --> -<h1>Data Mapper</h1> -<p>Data Mappers moves data between objects and a database while keeping them +<h1 id="140062">Data Mapper</h1> +<p id="700505" class="block-content">Data Mappers moves data between objects and a database while keeping them independent of each other and the mapper itself. If you started with <a href="?page=Database.ActiveRecord">Active Records</a>, you may eventually faced with more complex business @@ -12,28 +12,28 @@ that is, the object schema and the relational schema don't match up. </p> -<p>The Data Mapper separates the in-memory objects from the database. Its responsibility +<p id="700506" class="block-content">The Data Mapper separates the in-memory objects from the database. Its responsibility is to transfer data between the two and also to isolate them from each other. With Data Mapper the in-memory objects needn't know even that there's a database present; they need no SQL interface code, and certainly no knowledge of the database schema. (The database schema is always ignorant of the objects that use it.) </p> -<h2>When to Use It</h2> -<p>The primary occasion for using Data Mapper is when you want the database schema +<h2 id="140063">When to Use It</h2> +<p id="700507" class="block-content">The primary occasion for using Data Mapper is when you want the database schema and the object model to evolve independently. Data Mapper's primary benefit is that when working on the business (or domain) objects you can ignore the database, both in design and in the build and testing process. The domain objects have no idea what the database structure is, because all the correspondence is done by the mappers. </p> -<p>This helps you in the code because you can understand and work with the domain objects +<p id="700508" class="block-content">This helps you in the code because you can understand and work with the domain objects without having to understand how they're stored in the database. You can modify the business models or the database without having to alter either. With complicated mappings, particularly those involving <b>existing databases</b>, this is very valuable. </p> -<p>The price, of course, is the extra layer that you don't get with +<p id="700509" class="block-content">The price, of course, is the extra layer that you don't get with <a href="?page=Database.ActiveRecord">Active Record</a>, so the test for using these patterns is the complexity of the business logic. If you have fairly simple business logic, an <a href="?page=Database.ActiveRecord">Active Record</a> @@ -41,8 +41,8 @@ For more complicated logic a Data Mapper may be more suitable. </p> -<h2>SqlMap Data Mapper</h2> -<p>The SqlMap DataMapper framework makes it easier to use a database with a PHP application. +<h2 id="140064">SqlMap Data Mapper</h2> +<p id="700510" class="block-content">The SqlMap DataMapper framework makes it easier to use a database with a PHP application. SqlMap DataMapper couples objects with stored procedures or SQL statements using a XML descriptor. Simplicity is the biggest advantage of the SqlMap DataMapper over object relational mapping tools. To use SqlMap DataMapper you rely on your own objects, @@ -51,7 +51,7 @@ your fingertip </p> -<p> +<p id="700511" class="block-content"> <img src=<%~ diagram.png %> alt="SqlMap Data Mapper Overview" id="fig:sqlmap.png" class="figure"/> Here's a high level description of the work flow illustrated in the figure abov. @@ -59,23 +59,23 @@ used to set runtime values in your SQL statement or stored procedure. If a runtime value is not needed, the parameter can be omitted. </p> -<p>Execute the mapping by passing the parameter and the name you gave the statement or +<p id="700512" class="block-content">Execute the mapping by passing the parameter and the name you gave the statement or procedure in your XML descriptor. This step is where the magic happens. The framework will prepare the SQL statement or stored procedure, set any runtime values using your parameter, execute the procedure or statement, and return the result. </p> -<p>In the case of an update, the number of rows affected is returned. In the case of a +<p id="700513" class="block-content">In the case of an update, the number of rows affected is returned. In the case of a query, a single object, or a collection of objects is returned. Like the parameter, the result object, or collection of objects, can be a plain-old object or a primitive PHP type. </p> -<h2>Setting up a database connection and initializing the SqlMap</h2> -<p> +<h2 id="140065">Setting up a database connection and initializing the SqlMap</h2> +<p id="700514" class="block-content"> A database connection for SqlMap can be set as follows. See <a href="?page=Database.DAO">Establishing Database Connection</a> for futher details regarding creation of database connection in general. -<com:TTextHighlighter Language="php" CssClass="source"> +<com:TTextHighlighter Language="php" CssClass="source block-content" id="code_700166"> //create a connection and give it to the SqlMap manager. $dsn = 'pgsql:host=localhost;dbname=test'; //Postgres SQL $conn = new TDbConnection($dsn, 'dbuser','dbpass'); @@ -85,7 +85,7 @@ $sqlmap = $manager->getSqlMapGateway(); </com:TTextHighlighter> </p> -<p> +<p id="700515" class="block-content"> The <tt>TSqlMapManager</tt> is responsible for setting up the database connection and configuring the SqlMap with given XML file(s). The <tt>configureXml()</tt> method accepts a string that points to a SqlMap XML configuration file. Once @@ -93,11 +93,11 @@ $sqlmap = $manager->getSqlMapGateway(); of the SqlMap gateway interface (use this object to insert/delete/find records). </p> -<p> +<p id="700516" class="block-content"> SqlMap database connection can also be configured using a <tt><module></tt> tag in the <a href="?page=Configurations.AppConfig">application.xml</a> or <a href="?page=Configurations.PageConfig">config.xml</a> as follows. -<com:TTextHighlighter Language="xml" CssClass="source"> +<com:TTextHighlighter Language="xml" CssClass="source block-content" id="code_700167"> <modules> <module id="my-sqlmap" class="System.Data.SqlMap.TSqlMapConfig" EnableCache="true" ConfigFile="my-sqlmap.xml" > @@ -108,7 +108,7 @@ $sqlmap = $manager->getSqlMapGateway(); </com:TTextHighlighter> </p> -<p> +<p id="700517" class="block-content"> The <tt>ConfigFile</tt> attribute should point to a SqlMap configuration file (to be detailed later) either using absolute path, relative path or the Prado's namespace dot notation path (must omit the ".xml" extension). @@ -122,9 +122,9 @@ $sqlmap = $manager->getSqlMapGateway(); </div> </p> -<p>To obtain the SqlMap gateway interface from the <module> configuration, simply +<p id="700518" class="block-content">To obtain the SqlMap gateway interface from the <module> configuration, simply do, for example, -<com:TTextHighlighter Language="php" CssClass="source"> +<com:TTextHighlighter Language="php" CssClass="source block-content" id="code_700168"> class MyPage extends TPage { public function onLoad($param) @@ -137,11 +137,11 @@ class MyPage extends TPage </com:TTextHighlighter> </p> -<h2>A quick example</h2> -<p>Let us +<h2 id="140066">A quick example</h2> +<p id="700519" class="block-content">Let us consider the following "users" table that contains two columns named "username" and "email", where "username" is also the primary key. -<com:TTextHighlighter Language="sql" CssClass="source"> +<com:TTextHighlighter Language="sql" CssClass="source block-content" id="code_700169"> CREATE TABLE users ( username VARCHAR( 20 ) NOT NULL , @@ -150,9 +150,9 @@ CREATE TABLE users ); </com:TTextHighlighter> </p> -<p>Next we define our plain <tt>User</tt> class as follows. Notice that +<p id="700520" class="block-content">Next we define our plain <tt>User</tt> class as follows. Notice that the <tt>User</tt> is very simple. -<com:TTextHighlighter Language="php" CssClass="source"> +<com:TTextHighlighter Language="php" CssClass="source block-content" id="code_700170"> class User { public $username; @@ -162,9 +162,9 @@ class User </p> </p> -<p>Next, we need to define a SqlMap XMl configuration file, lets name +<p id="700521" class="block-content">Next, we need to define a SqlMap XMl configuration file, lets name the file as <tt>my-sqlmap.xml</tt> -<com:TTextHighlighter Language="xml" CssClass="source"> +<com:TTextHighlighter Language="xml" CssClass="source block-content" id="code_700171"> <?xml version="1.0" encoding="utf-8" ?> <sqlMapConfig> <select id="SelectUsers" resultClass="User"> @@ -173,12 +173,12 @@ class User </sqlMapConfig> </com:TTextHighlighter> </p> -<p>The <select> tag returns defines an SQL statement. The <tt>id</tt> +<p id="700522" class="block-content">The <select> tag returns defines an SQL statement. The <tt>id</tt> attribute will be used as the identifier for the query. The <tt>resultClass</tt> attribute value is the name of the class the the objects to be returned. We can now query the objects as follows: -<com:TTextHighlighter Language="php" CssClass="source"> +<com:TTextHighlighter Language="php" CssClass="source block-content" id="code_700172"> //assume that $sqlmap is an TSqlMapGateway instance $userList = $sqlmap->queryForList("SelectUsers"); @@ -187,18 +187,18 @@ $user = $sqlmap->queryForObject("SelectUsers"); </com:TTextHighlighter> </p> -<p>The above example shows demonstrates only a fraction of the capabilities +<p id="700523" class="block-content">The above example shows demonstrates only a fraction of the capabilities of the SqlMap Data Mapper. Further details can be found in the <a href="http://www.pradosoft.com/demo/sqlamp/">SqlMap Manual</a>. </p> -<h2>Combining SqlMap with Active Records</h2> -<p>The above example may seem trival and it also seems that there is +<h2 id="140067">Combining SqlMap with Active Records</h2> +<p id="700524" class="block-content">The above example may seem trival and it also seems that there is alot work just to retrieve some data. However, notice that the <tt>User</tt> class is totally unware of been stored in the database, and the database is unware of the <tt>User</tt> class. </p> -<p> +<p id="700525" class="block-content"> One of advantages of SqlMap is the ability to map complex object relationship, collections from an existing database. On the other hand, <a href="?page=Database.ActiveRecord">Active Record</a> @@ -208,9 +208,9 @@ $user = $sqlmap->queryForObject("SelectUsers"); complicated relationships and collections as Active Record objects and then using these Active Records to do the updates, inserts and deletes. </p> -<p>Continuing with the previous example, we change the definition of the +<p id="700526" class="block-content">Continuing with the previous example, we change the definition of the <tt>User</tt> class to become an Active Record. -<com:TTextHighlighter Language="php" CssClass="source"> +<com:TTextHighlighter Language="php" CssClass="source block-content" id="code_700173"> class UserRecord extends TActiveRecord { public $username; //the column named "username" in the "users" table @@ -229,9 +229,9 @@ class UserRecord extends TActiveRecord </com:TTextHighlighter> </p> -<p>We also need to change the definition of the SqlMap XML configuration. We +<p id="700527" class="block-content">We also need to change the definition of the SqlMap XML configuration. We just need to change the value of <tt>resultClass</tt> attribute to <tt>UserRecord</tt>. -<com:TTextHighlighter Language="xml" CssClass="source"> +<com:TTextHighlighter Language="xml" CssClass="source block-content" id="code_700174"> <?xml version="1.0" encoding="utf-8" ?> <sqlMapConfig> <select id="SelectUsers" resultClass="UserRecord"> @@ -242,10 +242,10 @@ class UserRecord extends TActiveRecord </p> -<p>The PHP code for retrieving the users remains the same, but SqlMap +<p id="700528" class="block-content">The PHP code for retrieving the users remains the same, but SqlMap returns Active Records instead, and we can take advantage of the Active Record methods. -<com:TTextHighlighter Language="php" CssClass="source"> +<com:TTextHighlighter Language="php" CssClass="source block-content" id="code_700175"> //assume that $sqlmap is an TSqlMapGateway instance $user = $sqlmap->queryForObject("SelectUsers"); @@ -254,8 +254,8 @@ $user->save(); //save it using Active Record </com:TTextHighlighter> </p> -<h2>References</h2> -<ul> +<h2 id="140068">References</h2> +<ul id="u1" class="block-content"> <li>Fowler et. al. <i>Patterns of Enterprise Application Architecture</i>, Addison Wesley, 2002.</li> <li>xxxx. <i>iBatis Data Mapper</i>, |