YII 类库手册

public function __construct($schema)
{
    $this->_schema=$schema;
    $this->_connection=$schema->getDbConnection();
}

public function applyCondition($sql,$condition)
{
    if($condition!='')
        return $sql.' WHERE '.$condition;
    else
        return $sql;
}

public function applyGroup($sql,$group)
{
    if($group!='')
        return $sql.' GROUP BY '.$group;
    else
        return $sql;
}

public function applyHaving($sql,$having)
{
    if($having!='')
        return $sql.' HAVING '.$having;
    else
        return $sql;
}

public function applyJoin($sql,$join)
{
    if($join!='')
        return $sql.' '.$join;
    else
        return $sql;
}

public function applyLimit($sql,$limit,$offset)
{
    if($limit>=0)
        $sql.=' LIMIT '.(int)$limit;
    if($offset>0)
        $sql.=' OFFSET '.(int)$offset;
    return $sql;
}

public function applyOrder($sql,$orderBy)
{
    if($orderBy!='')
        return $sql.' ORDER BY '.$orderBy;
    else
        return $sql;
}

public function bindValues($command, $values)
{
    if(($n=count($values))===0)
        return;
    if(isset($values[0])) // question mark placeholders
    {
        for($i=0;$i<$n;++$i)
            $command->bindValue($i+1,$values[$i]);
    }
    else // named placeholders
    {
        foreach($values as $name=>$value)
        {
            if($name[0]!==':')
                $name=':'.$name;
            $command->bindValue($name,$value);
        }
    }
}

public function createColumnCriteria($table,$columns,$condition='',$params=array(),$prefix=null)
{
    $this->ensureTable($table);
    $criteria=$this->createCriteria($condition,$params);
    if($criteria->alias!='')
        $prefix=$this->_schema->quoteTableName($criteria->alias).'.';
    $bindByPosition=isset($criteria->params[0]);
    $conditions=array();
    $values=array();
    $i=0;
    if($prefix===null)
        $prefix=$table->rawName.'.';
    foreach($columns as $name=>$value)
    {
        if(($column=$table->getColumn($name))!==null)
        {
            if(is_array($value))
                $conditions[]=$this->createInCondition($table,$name,$value,$prefix);
            else if($value!==null)
            {
                if($bindByPosition)
                {
                    $conditions[]=$prefix.$column->rawName.'=?';
                    $values[]=$value;
                }
                else
                {
                    $conditions[]=$prefix.$column->rawName.'='.self::PARAM_PREFIX.$i;
                    $values[self::PARAM_PREFIX.$i]=$value;
                    $i++;
                }
            }
            else
                $conditions[]=$prefix.$column->rawName.' IS NULL';
        }
        else
            throw new CDbException(Yii::t('yii','Table "{table}" does not have a column named "{column}".',
                array('{table}'=>$table->name,'{column}'=>$name)));
    }
    $criteria->params=array_merge($values,$criteria->params);
    if(isset($conditions[0]))
    {
        if($criteria->condition!='')
            $criteria->condition=implode(' AND ',$conditions).' AND ('.$criteria->condition.')';
        else
            $criteria->condition=implode(' AND ',$conditions);
    }
    return $criteria;
}

protected function createCompositeInCondition($table,$values,$prefix)
{
    $keyNames=array();
    foreach(array_keys($values[0]) as $name)
        $keyNames[]=$prefix.$table->columns[$name]->rawName;
    $vs=array();
    foreach($values as $value)
        $vs[]='('.implode(', ',$value).')';
    return '('.implode(', ',$keyNames).') IN ('.implode(', ',$vs).')';
}

public function createCountCommand($table,$criteria,$alias='t')
{
    $this->ensureTable($table);
    if($criteria->alias!='')
        $alias=$criteria->alias;
    $alias=$this->_schema->quoteTableName($alias);

    if(!empty($criteria->group) || !empty($criteria->having))
    {
        $select=is_array($criteria->select) ? implode(', ',$criteria->select) : $criteria->select;
        if($criteria->alias!='')
            $alias=$criteria->alias;
        $sql=($criteria->distinct ? 'SELECT DISTINCT':'SELECT')." {$select} FROM {$table->rawName} $alias";
        $sql=$this->applyJoin($sql,$criteria->join);
        $sql=$this->applyCondition($sql,$criteria->condition);
        $sql=$this->applyGroup($sql,$criteria->group);
        $sql=$this->applyHaving($sql,$criteria->having);
        $sql="SELECT COUNT(*) FROM ($sql) sq";
    }
    else
    {
        if(is_string($criteria->select) && stripos($criteria->select,'count')===0)
            $sql="SELECT ".$criteria->select;
        else if($criteria->distinct)
        {
            if(is_array($table->primaryKey))
            {
                $pk=array();
                foreach($table->primaryKey as $key)
                    $pk[]=$alias.'.'.$key;
                $pk=implode(', ',$pk);
            }
            else
                $pk=$alias.'.'.$table->primaryKey;
            $sql="SELECT COUNT(DISTINCT $pk)";
        }
        else
            $sql="SELECT COUNT(*)";
        $sql.=" FROM {$table->rawName} $alias";
        $sql=$this->applyJoin($sql,$criteria->join);
        $sql=$this->applyCondition($sql,$criteria->condition);
    }

    $command=$this->_connection->createCommand($sql);
    $this->bindValues($command,$criteria->params);
    return $command;
}

public function createCriteria($condition='',$params=array())
{
    if(is_array($condition))
        $criteria=new CDbCriteria($condition);
    else if($condition instanceof CDbCriteria)
        $criteria=clone $condition;
    else
    {
        $criteria=new CDbCriteria;
        $criteria->condition=$condition;
        $criteria->params=$params;
    }
    return $criteria;
}

public function createDeleteCommand($table,$criteria)
{
    $this->ensureTable($table);
    $sql="DELETE FROM {$table->rawName}";
    $sql=$this->applyJoin($sql,$criteria->join);
    $sql=$this->applyCondition($sql,$criteria->condition);
    $sql=$this->applyGroup($sql,$criteria->group);
    $sql=$this->applyHaving($sql,$criteria->having);
    $sql=$this->applyOrder($sql,$criteria->order);
    $sql=$this->applyLimit($sql,$criteria->limit,$criteria->offset);
    $command=$this->_connection->createCommand($sql);
    $this->bindValues($command,$criteria->params);
    return $command;
}

public function createFindCommand($table,$criteria,$alias='t')
{
    $this->ensureTable($table);
    $select=is_array($criteria->select) ? implode(', ',$criteria->select) : $criteria->select;
    if($criteria->alias!='')
        $alias=$criteria->alias;
    $alias=$this->_schema->quoteTableName($alias);

    // issue 1432: need to expand * when SQL has JOIN
    if($select==='*' && !empty($criteria->join))
    {
        $prefix=$alias.'.';
        $select=array();
        foreach($table->getColumnNames() as $name)
            $select[]=$prefix.$this->_schema->quoteColumnName($name);
        $select=implode(', ',$select);
    }

    $sql=($criteria->distinct ? 'SELECT DISTINCT':'SELECT')." {$select} FROM {$table->rawName} $alias";
    $sql=$this->applyJoin($sql,$criteria->join);
    $sql=$this->applyCondition($sql,$criteria->condition);
    $sql=$this->applyGroup($sql,$criteria->group);
    $sql=$this->applyHaving($sql,$criteria->having);
    $sql=$this->applyOrder($sql,$criteria->order);
    $sql=$this->applyLimit($sql,$criteria->limit,$criteria->offset);
    $command=$this->_connection->createCommand($sql);
    $this->bindValues($command,$criteria->params);
    return $command;
}

public function createInCondition($table,$columnName,$values,$prefix=null)
{
    if(($n=count($values))<1)
        return '0=1';

    $this->ensureTable($table);

    if($prefix===null)
        $prefix=$table->rawName.'.';

    $db=$this->_connection;

    if(is_array($columnName) && count($columnName)===1)
        $columnName=reset($columnName);

    if(is_string($columnName)) // simple key
    {
        if(!isset($table->columns[$columnName]))
            throw new CDbException(Yii::t('yii','Table "{table}" does not have a column named "{column}".',
            array('{table}'=>$table->name, '{column}'=>$columnName)));
        $column=$table->columns[$columnName];

        foreach($values as &$value)
        {
            $value=$column->typecast($value);
            if(is_string($value))
                $value=$db->quoteValue($value);
        }
        if($n===1)
            return $prefix.$column->rawName.($values[0]===null?' IS NULL':'='.$values[0]);
        else
            return $prefix.$column->rawName.' IN ('.implode(', ',$values).')';
    }
    else if(is_array($columnName)) // composite key: $values=array(array('pk1'=>'v1','pk2'=>'v2'),array(...))
    {
        foreach($columnName as $name)
        {
            if(!isset($table->columns[$name]))
                throw new CDbException(Yii::t('yii','Table "{table}" does not have a column named "{column}".',
                array('{table}'=>$table->name, '{column}'=>$name)));

            for($i=0;$i<$n;++$i)
            {
                if(isset($values[$i][$name]))
                {
                    $value=$table->columns[$name]->typecast($values[$i][$name]);
                    if(is_string($value))
                        $values[$i][$name]=$db->quoteValue($value);
                    else
                        $values[$i][$name]=$value;
                }
                else
                    throw new CDbException(Yii::t('yii','The value for the column "{column}" is not supplied when querying the table "{table}".',
                        array('{table}'=>$table->name,'{column}'=>$name)));
            }
        }
        if(count($values)===1)
        {
            $entries=array();
            foreach($values[0] as $name=>$value)
                $entries[]=$prefix.$table->columns[$name]->rawName.($value===null?' IS NULL':'='.$value);
            return implode(' AND ',$entries);
        }

        return $this->createCompositeInCondition($table,$values,$prefix);
    }
    else
        throw new CDbException(Yii::t('yii','Column name must be either a string or an array.'));
}

public function createInsertCommand($table,$data)
{
    $this->ensureTable($table);
    $fields=array();
    $values=array();
    $placeholders=array();
    $i=0;
    foreach($data as $name=>$value)
    {
        if(($column=$table->getColumn($name))!==null && ($value!==null || $column->allowNull))
        {
            $fields[]=$column->rawName;
            if($value instanceof CDbExpression)
            {
                $placeholders[]=$value->expression;
                foreach($value->params as $n=>$v)
                    $values[$n]=$v;
            }
            else
            {
                $placeholders[]=self::PARAM_PREFIX.$i;
                $values[self::PARAM_PREFIX.$i]=$column->typecast($value);
                $i++;
            }
        }
    }
    if($fields===array())
    {
        $pks=is_array($table->primaryKey) ? $table->primaryKey : array($table->primaryKey);
        foreach($pks as $pk)
        {
            $fields[]=$table->getColumn($pk)->rawName;
            $placeholders[]='NULL';
        }
    }
    $sql="INSERT INTO {$table->rawName} (".implode(', ',$fields).') VALUES ('.implode(', ',$placeholders).')';
    $command=$this->_connection->createCommand($sql);

    foreach($values as $name=>$value)
        $command->bindValue($name,$value);

    return $command;
}

public function createPkCondition($table,$values,$prefix=null)
{
    $this->ensureTable($table);
    return $this->createInCondition($table,$table->primaryKey,$values,$prefix);
}

public function createPkCriteria($table,$pk,$condition='',$params=array(),$prefix=null)
{
    $this->ensureTable($table);
    $criteria=$this->createCriteria($condition,$params);
    if($criteria->alias!='')
        $prefix=$this->_schema->quoteTableName($criteria->alias).'.';
    if(!is_array($pk)) // single key
        $pk=array($pk);
    if(is_array($table->primaryKey) && !isset($pk[0]) && $pk!==array()) // single composite key
        $pk=array($pk);
    $condition=$this->createInCondition($table,$table->primaryKey,$pk,$prefix);
    if($criteria->condition!='')
        $criteria->condition=$condition.' AND ('.$criteria->condition.')';
    else
        $criteria->condition=$condition;

    return $criteria;
}

public function createSearchCondition($table,$columns,$keywords,$prefix=null,$caseSensitive=true)
{
    $this->ensureTable($table);
    if(!is_array($keywords))
        $keywords=preg_split('/\s+/u',$keywords,-1,PREG_SPLIT_NO_EMPTY);
    if(empty($keywords))
        return '';
    if($prefix===null)
        $prefix=$table->rawName.'.';
    $conditions=array();
    foreach($columns as $name)
    {
        if(($column=$table->getColumn($name))===null)
            throw new CDbException(Yii::t('yii','Table "{table}" does not have a column named "{column}".',
                array('{table}'=>$table->name,'{column}'=>$name)));
        $condition=array();
        foreach($keywords as $keyword)
        {
            $keyword='%'.strtr($keyword,array('%'=>'\%', '_'=>'\_')).'%';
            if($caseSensitive)
                $condition[]=$prefix.$column->rawName.' LIKE '.$this->_connection->quoteValue('%'.$keyword.'%');
            else
                $condition[]='LOWER('.$prefix.$column->rawName.') LIKE LOWER('.$this->_connection->quoteValue('%'.$keyword.'%').')';
        }
        $conditions[]=implode(' AND ',$condition);
    }
    return '('.implode(' OR ',$conditions).')';
}

public function createSqlCommand($sql,$params=array())
{
    $command=$this->_connection->createCommand($sql);
    $this->bindValues($command,$params);
    return $command;
}

public function createUpdateCommand($table,$data,$criteria)
{
    $this->ensureTable($table);
    $fields=array();
    $values=array();
    $bindByPosition=isset($criteria->params[0]);
    $i=0;
    foreach($data as $name=>$value)
    {
        if(($column=$table->getColumn($name))!==null)
        {
            if($value instanceof CDbExpression)
            {
                $fields[]=$column->rawName.'='.$value->expression;
                foreach($value->params as $n=>$v)
                    $values[$n]=$v;
            }
            else if($bindByPosition)
            {
                $fields[]=$column->rawName.'=?';
                $values[]=$column->typecast($value);
            }
            else
            {
                $fields[]=$column->rawName.'='.self::PARAM_PREFIX.$i;
                $values[self::PARAM_PREFIX.$i]=$column->typecast($value);
                $i++;
            }
        }
    }
    if($fields===array())
        throw new CDbException(Yii::t('yii','No columns are being updated for table "{table}".',
            array('{table}'=>$table->name)));
    $sql="UPDATE {$table->rawName} SET ".implode(', ',$fields);
    $sql=$this->applyJoin($sql,$criteria->join);
    $sql=$this->applyCondition($sql,$criteria->condition);
    $sql=$this->applyOrder($sql,$criteria->order);
    $sql=$this->applyLimit($sql,$criteria->limit,$criteria->offset);

    $command=$this->_connection->createCommand($sql);
    $this->bindValues($command,array_merge($values,$criteria->params));

    return $command;
}

public function createUpdateCounterCommand($table,$counters,$criteria)
{
    $this->ensureTable($table);
    $fields=array();
    foreach($counters as $name=>$value)
    {
        if(($column=$table->getColumn($name))!==null)
        {
            $value=(int)$value;
            if($value<0)
                $fields[]="{$column->rawName}={$column->rawName}-".(-$value);
            else
                $fields[]="{$column->rawName}={$column->rawName}+".$value;
        }
    }
    if($fields!==array())
    {
        $sql="UPDATE {$table->rawName} SET ".implode(', ',$fields);
        $sql=$this->applyJoin($sql,$criteria->join);
        $sql=$this->applyCondition($sql,$criteria->condition);
        $sql=$this->applyOrder($sql,$criteria->order);
        $sql=$this->applyLimit($sql,$criteria->limit,$criteria->offset);
        $command=$this->_connection->createCommand($sql);
        $this->bindValues($command,$criteria->params);
        return $command;
    }
    else
        throw new CDbException(Yii::t('yii','No counter columns are being updated for table "{table}".',
            array('{table}'=>$table->name)));
}

protected function ensureTable(&$table)
{
    if(is_string($table) && ($table=$this->_schema->getTable($tableName=$table))===null)
        throw new CDbException(Yii::t('yii','Table "{table}" does not exist.',
            array('{table}'=>$tableName)));
}

public function getDbConnection()
{
    return $this->_connection;
}

public function getLastInsertID($table)
{
    $this->ensureTable($table);
    if($table->sequenceName!==null)
        return $this->_connection->getLastInsertID($table->sequenceName);
    else
        return null;
}

public function getSchema()
{
    return $this->_schema;
}