mirror of
https://github.com/yiisoft/yii.git
synced 2026-03-07 08:36:55 +01:00
127 lines
3.2 KiB
PHP
127 lines
3.2 KiB
PHP
<?php
|
|
/**
|
|
* CDbSchema class file.
|
|
*
|
|
* @author Qiang Xue <qiang.xue@gmail.com>
|
|
* @link http://www.yiiframework.com/
|
|
* @copyright Copyright © 2008 Yii Software LLC
|
|
* @license http://www.yiiframework.com/license/
|
|
*/
|
|
|
|
/**
|
|
* CDbSchema is the base class for retrieving metadata information.
|
|
*
|
|
* @author Qiang Xue <qiang.xue@gmail.com>
|
|
* @version $Id$
|
|
* @package system.db.schema
|
|
* @since 1.0
|
|
*/
|
|
abstract class CDbSchema extends CComponent
|
|
{
|
|
private $_tables=array();
|
|
private $_connection;
|
|
private $_builder;
|
|
private $_cacheExclude=array();
|
|
|
|
/**
|
|
* Creates a table instance representing the metadata for the named table.
|
|
* @return CDbTableSchema driver dependent table metadata, null if the table does not exist.
|
|
*/
|
|
abstract protected function createTable($name);
|
|
|
|
/**
|
|
* Constructor.
|
|
* @param CDbConnection database connection.
|
|
*/
|
|
public function __construct($conn)
|
|
{
|
|
$conn->setActive(true);
|
|
$this->_connection=$conn;
|
|
foreach($conn->schemaCachingExclude as $name)
|
|
$this->_cacheExclude[$name]=true;
|
|
}
|
|
|
|
/**
|
|
* @return CDbConnection database connection. The connection is active.
|
|
*/
|
|
public function getDbConnection()
|
|
{
|
|
return $this->_connection;
|
|
}
|
|
|
|
/**
|
|
* Obtains the metadata for the named table.
|
|
* @param string table name
|
|
* @return CDbTableSchema table metadata. Null if the named table does not exist.
|
|
*/
|
|
public function getTable($name)
|
|
{
|
|
if(isset($this->_tables[$name]))
|
|
return $this->_tables[$name];
|
|
else if(!isset($this->_cacheExclude[$name]) && ($duration=$this->_connection->schemaCachingDuration)>0 && ($cache=Yii::app()->getCache())!==null)
|
|
{
|
|
$key='yii:dbschema'.$this->_connection->connectionString.':'.$this->_connection->username.':'.$name;
|
|
if(($table=$cache->get($key))===false)
|
|
{
|
|
$table=$this->createTable($name);
|
|
$cache->set($key,$table,$duration);
|
|
}
|
|
return $this->_tables[$name]=$table;
|
|
}
|
|
else
|
|
return $this->_tables[$name]=$this->createTable($name);
|
|
}
|
|
|
|
/**
|
|
* @return CDbCommandBuilder the SQL command builder for this connection.
|
|
*/
|
|
public function getCommandBuilder()
|
|
{
|
|
if($this->_builder!==null)
|
|
return $this->_builder;
|
|
else
|
|
return $this->_builder=$this->createCommandBuilder();
|
|
}
|
|
|
|
/**
|
|
* Creates a command builder for the database.
|
|
* This method may be overridden by child classes to create a DBMS-specific command builder.
|
|
* @return CDbCommandBuilder command builder instance
|
|
*/
|
|
protected function createCommandBuilder()
|
|
{
|
|
return new CDbCommandBuilder($this);
|
|
}
|
|
|
|
/**
|
|
* Refreshes the schema.
|
|
* This method resets the loaded table metadata and command builder
|
|
* so that they can be recreated to reflect the change of schema.
|
|
*/
|
|
public function refresh()
|
|
{
|
|
$this->_tables=array();
|
|
$this->_builder=null;
|
|
}
|
|
|
|
/**
|
|
* Quotes a table name for use in a query.
|
|
* @param string table name
|
|
* @return string the properly quoted table name
|
|
*/
|
|
public function quoteTableName($name)
|
|
{
|
|
return "'".$name."'";
|
|
}
|
|
|
|
/**
|
|
* Quotes a column name for use in a query.
|
|
* @param string column name
|
|
* @return string the properly quoted column name
|
|
*/
|
|
public function quoteColumnName($name)
|
|
{
|
|
return '"'.$name.'"';
|
|
}
|
|
}
|