<?php
/**
* CMysqlSchema class file.
*
* @author Qiang Xue <[email protected]>
* @link http://www.yiiframework.com/
* @copyright Copyright © 2008-2011 Yii Software LLC
* @license http://www.yiiframework.com/license/
*/
/**
* CMysqlSchema is the class for retrieving metadata information from a MySQL database (version 4.1.x and 5.x).
*
* @author Qiang Xue <[email protected]>
* @package system.db.schema.mysql
* @since 1.0
*/
class CMysqlSchema extends CDbSchema
{
/**
* @var array the abstract column types mapped to physical column types.
* @since 1.1.6
*/
public $columnTypes=array(
'pk' => 'int(11) NOT NULL AUTO_INCREMENT PRIMARY KEY',
'string' => 'varchar(255)',
'text' => 'text',
'integer' => 'int(11)',
'float' => 'float',
'decimal' => 'decimal',
'datetime' => 'datetime',
'timestamp' => 'timestamp',
'time' => 'time',
'date' => 'date',
'binary' => 'blob',
'boolean' => 'tinyint(1)',
'money' => 'decimal(19,4)',
);
/**
* Quotes a table name for use in a query.
* A simple table name does not schema prefix.
* @param string $name table name
* @return string the properly quoted table name
* @since 1.1.6
*/
public function quoteSimpleTableName($name)
{
return '`'.$name.'`';
}
/**
* Quotes a column name for use in a query.
* A simple column name does not contain prefix.
* @param string $name column name
* @return string the properly quoted column name
* @since 1.1.6
*/
public function quoteSimpleColumnName($name)
{
return '`'.$name.'`';
}
/**
* Compares two table names.
* The table names can be either quoted or unquoted. This method
* will consider both cases.
* @param string $name1 table name 1
* @param string $name2 table name 2
* @return boolean whether the two table names refer to the same table.
*/
public function compareTableNames($name1,$name2)
{
return parent::compareTableNames(strtolower($name1),strtolower($name2));
}
/**
* Resets the sequence value of a table's primary key.
* The sequence will be reset such that the primary key of the next new row inserted
* will have the specified value or 1.
* @param CDbTableSchema $table the table schema whose primary key sequence will be reset
* @param mixed $value the value for the primary key of the next new row inserted. If this is not set,
* the next new row's primary key will have a value 1.
* @since 1.1
*/
public function resetSequence($table,$value=null)
{
if($table->sequenceName!==null)
{
if($value===null)
$value=$this->getDbConnection()->createCommand("SELECT MAX(`{$table->primaryKey}`) FROM {$table->rawName}")->queryScalar()+1;
else
$value=(int)$value;
$this->getDbConnection()->createCommand("ALTER TABLE {$table->rawName} AUTO_INCREMENT=$value")->execute();
}
}
/**
* Enables or disables integrity check.
* @param boolean $check whether to turn on or off the integrity check.
* @param string $schema the schema of the tables. Defaults to empty string, meaning the current or default schema.
* @since 1.1
*/
public function checkIntegrity($check=true,$schema='')
{
$this->getDbConnection()->createCommand('SET FOREIGN_KEY_CHECKS='.($check?1:0))->execute();
}
/**
* Loads the metadata for the specified table.
* @param string $name table name
* @return CMysqlTableSchema driver dependent table metadata. Null if the table does not exist.
*/
protected function loadTable($name)
{
$table=new CMysqlTableSchema;
$this->resolveTableNames($table,$name);
if($this->findColumns($table))
{
$this->findConstraints($table);
return $table;
}
else
return null;
}
/**
* Generates various kinds of table names.
* @param CMysqlTableSchema $table the table instance
* @param string $name the unquoted table name
*/
protected function resolveTableNames($table,$name)
{
$parts=explode('.',str_replace(array('`','"'),'',$name));
if(isset($parts[1]))
{
$table->schemaName=$parts[0];
$table->name=$parts[1];
$table->rawName=$this->quoteTableName($table->schemaName).'.'.$this->quoteTableName($table->name);
}
else
{
$table->name=$parts[0];
$table->rawName=$this->quoteTableName($table->name);
}
}
/**
* Collects the table column metadata.
* @param CMysqlTableSchema $table the table metadata
* @return boolean whether the table exists in the database
*/
protected function findColumns($table)
{
$sql='SHOW FULL COLUMNS FROM '.$table->rawName;
try
{
$columns=$this->getDbConnection()->createCommand($sql)->queryAll();
}
catch(Exception $e)
{
return false;
}
foreach($columns as $column)
{
$c=$this->createColumn($column);
$table->columns[$c->name]=$c;
if($c->isPrimaryKey)
{
if($table->primaryKey===null)
$table->primaryKey=$c->name;
elseif(is_string($table->primaryKey))
$table->primaryKey=array($table->primaryKey,$c->name);
else
$table->primaryKey[]=$c->name;
if($c->autoIncrement)
$table->sequenceName='';
}
}
return true;
}
/**
* Creates a table column.
* @param array $column column metadata
* @return CDbColumnSchema normalized column metadata
*/
protected function createColumn($column)
{
$c=new CMysqlColumnSchema;
$c->name=$column['Field'];
$c->rawName=$this->quoteColumnName($c->name);
$c->allowNull=$column['Null']==='YES';
$c->isPrimaryKey=strpos($column['Key'],'PRI')!==false;
$c->isForeignKey=false;
$c->init($column['Type'],$column['Default']);
$c->autoIncrement=strpos(strtolower($column['Extra']),'auto_increment')!==false;
$c->comment=$column['Comment'];
return $c;
}
/**
* @return float server version.
*/
protected function getServerVersion()
{
$version=$this->getDbConnection()->getAttribute(PDO::ATTR_SERVER_VERSION);
$digits=array();
preg_match('/(\d+)\.(\d+)\.(\d+)/', $version, $digits);
return floatval($digits[1].'.'.$digits[2].$digits[3]);
}
/**
* Collects the foreign key column details for the given table.
* @param CMysqlTableSchema $table the table metadata
*/
protected function findConstraints($table)
{
$row=$this->getDbConnection()->createCommand('SHOW CREATE TABLE '.$table->rawName)->queryRow();
$matches=array();
$regexp='/FOREIGN KEY\s+\(([^\)]+)\)\s+REFERENCES\s+([^\(^\s]+)\s*\(([^\)]+)\)/mi';
foreach($row as $sql)
{
if(preg_match_all($regexp,$sql,$matches,PREG_SET_ORDER))
break;
}
foreach($matches as $match)
{
$keys=array_map('trim',explode(',',str_replace(array('`','"'),'',$match[1])));
$fks=array_map('trim',explode(',',str_replace(array('`','"'),'',$match[3])));
foreach($keys as $k=>$name)
{
$table->foreignKeys[$name]=array(str_replace(array('`','"'),'',$match[2]),$fks[$k]);
if(isset($table->columns[$name]))
$table->columns[$name]->isForeignKey=true;
}
}
}
/**
* Returns all table names in the database.
* @param string $schema the schema of the tables. Defaults to empty string, meaning the current or default schema.
* If not empty, the returned table names will be prefixed with the schema name.
* @return array all table names in the database.
*/
protected function findTableNames($schema='')
{
if($schema==='')
return $this->getDbConnection()->createCommand('SHOW TABLES')->queryColumn();
$names=$this->getDbConnection()->createCommand('SHOW TABLES FROM '.$this->quoteTableName($schema))->queryColumn();
foreach($names as &$name)
$name=$schema.'.'.$name;
return $names;
}
/**
* Creates a command builder for the database.
* This method overrides parent implementation in order to create a MySQL specific command builder
* @return CDbCommandBuilder command builder instance
* @since 1.1.13
*/
protected function createCommandBuilder()
{
return new CMysqlCommandBuilder($this);
}
/**
* Builds a SQL statement for renaming a column.
* @param string $table the table whose column is to be renamed. The name will be properly quoted by the method.
* @param string $name the old name of the column. The name will be properly quoted by the method.
* @param string $newName the new name of the column. The name will be properly quoted by the method.
* @return string the SQL statement for renaming a DB column.
* @since 1.1.6
*/
public function renameColumn($table, $name, $newName)
{
$db=$this->getDbConnection();
$row=$db->createCommand('SHOW CREATE TABLE '.$db->quoteTableName($table))->queryRow();
if($row===false)
throw new CDbException(Yii::t('yii','Unable to find "{column}" in table "{table}".',array('{column}'=>$name,'{table}'=>$table)));
if(isset($row['Create Table']))
$sql=$row['Create Table'];
else
{
$row=array_values($row);
$sql=$row[1];
}
if(preg_match_all('/^\s*[`"](.*?)[`"]\s+(.*?),?$/m',$sql,$matches))
{
foreach($matches[1] as $i=>$c)
{
if($c===$name)
{
return "ALTER TABLE ".$db->quoteTableName($table)
. " CHANGE ".$db->quoteColumnName($name)
. ' '.$db->quoteColumnName($newName).' '.$matches[2][$i];
}
}
}
// try to give back a SQL anyway
return "ALTER TABLE ".$db->quoteTableName($table)
. " CHANGE ".$db->quoteColumnName($name).' '.$newName;
}
/**
* Builds a SQL statement for dropping a foreign key constraint.
* @param string $name the name of the foreign key constraint to be dropped. The name will be properly quoted by the method.
* @param string $table the table whose foreign is to be dropped. The name will be properly quoted by the method.
* @return string the SQL statement for dropping a foreign key constraint.
* @since 1.1.6
*/
public function dropForeignKey($name, $table)
{
return 'ALTER TABLE '.$this->quoteTableName($table)
.' DROP FOREIGN KEY '.$this->quoteColumnName($name);
}
/**
* Builds a SQL statement for removing a primary key constraint to an existing table.
* @param string $name the name of the primary key constraint to be removed.
* @param string $table the table that the primary key constraint will be removed from.
* @return string the SQL statement for removing a primary key constraint from an existing table.
* @since 1.1.13
*/
public function dropPrimaryKey($name,$table)
{
return 'ALTER TABLE ' . $this->quoteTableName($table) . ' DROP PRIMARY KEY';
}
}