diff options
author | xue <> | 2007-09-28 18:08:20 +0000 |
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committer | xue <> | 2007-09-28 18:08:20 +0000 |
commit | 199fc1254f84f851a2894df94487a45ed68f7c98 (patch) | |
tree | 55f899a4ed1a885ea2334db959acbe91e5e573a3 /demos/quickstart/protected/pages | |
parent | 4b292ae910c08c68ee62e5a96d7b879573921eee (diff) |
Fixed #665.
Diffstat (limited to 'demos/quickstart/protected/pages')
-rw-r--r-- | demos/quickstart/protected/pages/Database/ActiveRecord.page | 57 | ||||
-rw-r--r-- | demos/quickstart/protected/pages/GettingStarted/NewFeatures.page | 1 |
2 files changed, 49 insertions, 9 deletions
diff --git a/demos/quickstart/protected/pages/Database/ActiveRecord.page b/demos/quickstart/protected/pages/Database/ActiveRecord.page index 481985e9..a28c3d5e 100644 --- a/demos/quickstart/protected/pages/Database/ActiveRecord.page +++ b/demos/quickstart/protected/pages/Database/ActiveRecord.page @@ -52,21 +52,21 @@ </ul> <h2>Design Implications</h2> <p> -Prado's implementation of Active Record does not maintain referential identity. Each object obtained using -Active Record is a copy of the data in the database. For example, If you ask for -a particular customer and get back a <tt>Customer</tt> object, the next time you ask for +Prado's implementation of Active Record does not maintain referential identity. Each object obtained using +Active Record is a copy of the data in the database. For example, If you ask for +a particular customer and get back a <tt>Customer</tt> object, the next time you ask for that customer you get back another instance of a <tt>Customer</tt> object. This implies that a strict comparison (i.e., using <tt>===</tt>) will return false, while loose comparison (i.e., using <tt>==</tt>) will -return true if the object values are equal by loose comparison. +return true if the object values are equal by loose comparison. <p> <p> This is design implication related to the following question. -<i>"Do you think of the customer as an object, of which there's only one, +<i>"Do you think of the customer as an object, of which there's only one, or do you think of the objects you operate on as <b>copies</b> of the database?"</i> -Other O/R mappings will imply that there is only one Customer object with custID 100, and it literally is that customer. -If you get the customer and change a field on it, then you have now changed that customer. -<i>"That constrasts with: you have changed this copy of the customer, but not that copy. -And if two people update the customer on two copies of the object, whoever updates first, +Other O/R mappings will imply that there is only one Customer object with custID 100, and it literally is that customer. +If you get the customer and change a field on it, then you have now changed that customer. +<i>"That constrasts with: you have changed this copy of the customer, but not that copy. +And if two people update the customer on two copies of the object, whoever updates first, or maybe last, wins."</i> [A. Hejlsberg 2003] </p> @@ -1059,6 +1059,45 @@ arrays. E.g. <tt>$player->skills[] = new SkillRecord()</tt>. If <tt>array</tt> w will be thrown. </p> +<h2>Column Mapping</h2> +<p> +Since v3.1.1, Active Record starts to support column mapping. Column mapping allows developers +to address columns in Active Record using a more consistent naming convention. In particular, +using column mapping, one can access a column using whatever name he likes, rather than limited by +the name defined in the database schema. +</p> +<p> +To use column mapping, declare a static array named <tt>COLUMN_MAPPING</tt> in the Active Record class. +The keys of the array are column names (called <i>physical column names</i>) as defined in the database +schema, while the values are corresponding property names (called <i>logical column names</i>) defined +in the Active Record class. The property names can be either public class member variable names or +component property names defined via getters/setters. If a physical column name happens to be the same +as the logical column name, they do not need to be listed in <tt>COLUMN_MAPPING</tt>. +</p> +<com:TTextHighlighter Language="php" CssClass="source block-content"> +class UserRecord extends TActiveRecord +{ + const TABLE='users'; + protected static $COLUMN_MAPPING=array + ( + 'user_id'=>'id', + 'email_address'=>'email', + 'first_name'=>'firstName', + 'last_name'=>'lastName', + ); + public $id; + public $username; // the physical and logical column names are the same + public $email; + public $firstName; + public $lastName; + //.... +} +</com:TTextHighlighter> +<p> +With the above column mapping, we can address <tt>first_name</tt> using <tt>$userRecord->firstName</tt> +instead of <tt>$userRecord->first_name</tt>. This helps separation of logic and model. +</p> + <h2 id="138054">References</h2> <ul id="u3" class="block-content"> <li>Fowler et. al. <i>Patterns of Enterprise Application Architecture</i>, diff --git a/demos/quickstart/protected/pages/GettingStarted/NewFeatures.page b/demos/quickstart/protected/pages/GettingStarted/NewFeatures.page index 9db74476..595bda00 100644 --- a/demos/quickstart/protected/pages/GettingStarted/NewFeatures.page +++ b/demos/quickstart/protected/pages/GettingStarted/NewFeatures.page @@ -19,6 +19,7 @@ This page summarizes the main new features that are introduced in each PRADO rel <li>Added a new page state persister <tt>TCachePageStatePersister</tt>. It allows page state to be stored using a cache module (e.g. TMemCache, TDbCache, etc.)
<li>Added support to the <a href="?page=Advanced.Auth">auth framework</a> to allow remembering login.</li>
<li>Added support to display a prompt item in TDropDownList and TListBox (something like 'Please select:' as the first list item.)</li>
+<li>Added support to <a href="?page=Database.ActiveRecord">column mapping in Active Record</a>.</li>
</ul>
<h2 id="8006">Version 3.1.0</h2>
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