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-rwxr-xr-xframework/Db/schema/TDbSchema.php193
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diff --git a/framework/Db/schema/TDbSchema.php b/framework/Db/schema/TDbSchema.php
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+<?php
+/**
+ * TDbSchema class file.
+ *
+ * @author Qiang Xue <qiang.xue@gmail.com>
+ * @link http://www.yiiframework.com/
+ * @copyright Copyright &copy; 2008-2009 Yii Software LLC
+ * @license http://www.yiiframework.com/license/
+ */
+
+prado::using('System.db.schema.TDbCommandBuilder');
+
+/**
+ * TDbSchema 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 TDbSchema extends TComponent
+{
+ private $_tableNames=array();
+ private $_tables=array();
+ private $_connection;
+ private $_builder;
+ private $_cacheExclude=array();
+
+ /**
+ * Creates a table instance representing the metadata for the named table.
+ * @return TDbTableSchema driver dependent table metadata, null if the table does not exist.
+ */
+ abstract protected function createTable($name);
+
+ /**
+ * Constructor.
+ * @param TDbConnection database connection.
+ */
+ public function __construct($conn)
+ {
+ $conn->setActive(true);
+ $this->_connection=$conn;
+ foreach($conn->schemaCachingExclude as $name)
+ $this->_cacheExclude[$name]=true;
+ }
+
+ /**
+ * @return TDbConnection database connection. The connection is active.
+ */
+ public function getDbConnection()
+ {
+ return $this->_connection;
+ }
+
+ /**
+ * Obtains the metadata for the named table.
+ * @param string table name
+ * @return TDbTableSchema table metadata. Null if the named table does not exist.
+ */
+ public function getTable($name)
+ {
+ if(isset($this->_tables[$name]))
+ return $this->_tables[$name];
+ else if(!isset($this->_cacheExclude[$name]) && ($duration=$this->_connection->schemaCachingDuration)>0 && ($cache=prado::getApplication()->getCache())!==null)
+ {
+ $key='prado:dbschema'.$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);
+ }
+
+ /**
+ * Returns the metadata for all tables in the database.
+ * @param string the schema of the tables. Defaults to empty string, meaning the current or default schema.
+ * @return array the metadata for all tables in the database.
+ * Each array element is an instance of {@link TDbTableSchema} (or its child class).
+ * The array keys are table names.
+ * @since 1.0.2
+ */
+ public function getTables($schema='')
+ {
+ $tables=array();
+ foreach($this->getTableNames($schema) as $name)
+ $tables[$name]=$this->getTable($name);
+ return $tables;
+ }
+
+ /**
+ * Returns all table names in the database.
+ * @param string the schema of the tables. Defaults to empty string, meaning the current or default schema.
+ * If not empty, the returned table names will be prefixed with the schema name.
+ * @return array all table names in the database.
+ * @since 1.0.2
+ */
+ public function getTableNames($schema='')
+ {
+ if(!isset($this->_tableNames[$schema]))
+ $this->_tableNames[$schema]=$this->findTableNames($schema);
+ return $this->_tableNames[$schema];
+ }
+
+ /**
+ * @return TDbCommandBuilder the SQL command builder for this connection.
+ */
+ public function getCommandBuilder()
+ {
+ if($this->_builder!==null)
+ return $this->_builder;
+ else
+ return $this->_builder=$this->createCommandBuilder();
+ }
+
+ /**
+ * 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 '"'.$name.'"';
+ }
+
+ /**
+ * Compares two table names.
+ * The table names can be either quoted or unquoted. This method
+ * will consider both cases.
+ * @param string table name 1
+ * @param string table name 2
+ * @return boolean whether the two table names refer to the same table.
+ */
+ public function compareTableNames($name1,$name2)
+ {
+ $name1=str_replace(array('"','`',"'"),'',$name1);
+ $name2=str_replace(array('"','`',"'"),'',$name2);
+ if(($pos=strrpos($name1,'.'))!==false)
+ $name1=substr($name1,$pos+1);
+ if(($pos=strrpos($name2,'.'))!==false)
+ $name2=substr($name2,$pos+1);
+ return $name1===$name2;
+ }
+
+ /**
+ * Creates a command builder for the database.
+ * This method may be overridden by child classes to create a DBMS-specific command builder.
+ * @return TDbCommandBuilder command builder instance
+ */
+ protected function createCommandBuilder()
+ {
+ return new TDbCommandBuilder($this);
+ }
+
+ /**
+ * Returns all table names in the database.
+ * This method should be overridden by child classes in order to support this feature
+ * because the default implemenation simply throws an exception.
+ * @param string the schema of the tables. Defaults to empty string, meaning the current or default schema.
+ * If not empty, the returned table names will be prefixed with the schema name.
+ * @return array all table names in the database.
+ * @since 1.0.2
+ */
+ protected function findTableNames($schema='')
+ {
+ throw new TDbException('{0} does not support fetching all table names.',
+ get_class($this));
+ }
+}