yii 多表联合查询的几种方法

 

yii多表联合查询，

第一种，用command，自己拼接sql语句执行查询

 

第二种，用AR，model需继承下面的ar，执行queryall或queryrow方法

<?php

//application/components/BaseActiveRecord.php

class BaseActiveRecord extends CActiveRecord{



    /**

     * Returns the static model of the specified AR class.

     * The model returned is a static instance of the AR class.

     * It is provided for invoking class-level methods (something similar to static class methods.)

     *

     * <pre>

     * public static function model($className=__CLASS__)

     * {

     *     return parent::model($className);

     * }

     * </pre>

     *

     * @param string $className active record class name.

     * @return DBActiveRecord active record model instance.

     */

    public static function model($className=__CLASS__)

    {

        return parent::model($className);

    }



    

    /**

     * 获取字段rawName加表别名前缀,主要联表时候防止where条件中字段冲突用的

     * @param string $columnName

     * @return string

     */

    public function getColumnRawName($columnName)

    {

        $prefix = $this->getTableAlias(true) . '.';

        $columns = $this->tableSchema->columns;

        if (isset($columns[$columnName]))

        {

            return $prefix.$columns[$columnName]->rawName;

        }

        else

        {

            return $columnName;

        }

    }

    

    /**

     * 

     * @param mixed $criteria

     */

    public function queryAll($criteria = NULL)

    {

        if ( ! empty($criteria))

        {

            $this->getDbCriteria()->mergeWith($criteria);

        }

        

        $result = $this->getCommandBuilder()

            ->createFindCommand($this->tableSchema, $this->getDbCriteria())

            ->queryAll();

        

        $this->setDbCriteria(NULL);

        

        return $result;

    }

    

    public function queryRow($criteria = NULL)

    {

        if ($criteria != NULL)

        {

            $this->getDbCriteria()->mergeWith($criteria);

        }

        

        $result = $this->getCommandBuilder()

            ->createFindCommand($this->tableSchema, $this->getDbCriteria())

            ->queryRow();

        

        $this->setDbCriteria(NULL);

        

        return $result;

    }

    

    public function compare($column, $value, $partialMatch = FALSE, $operator = 'AND')

    {

        $criteria = new \CDbCriteria;

        $column = $this->getColumnRawName($column);

        

        if ($value === array())

        {

            $criteria->condition = "1 = 0";

        }

        else if ($value === '')

        {

            $criteria->condition = $column." = ''";

        }

        else

        {

            $criteria->compare($column, $value, $partialMatch, $operator, TRUE);

        }

        

        $this->getDbCriteria()->mergeWith($criteria);

        

        return $this;

    }

    

    

}

还有一种就是用ar的relation，做的关联容易忘记，这种不好用！