使用Zend Framework 1.6.2添加二阶字段时发生歧义错误

Question

When I echo the sql using echo $select->__toString() :

SELECT `a`.`ChannelID`,
       `a`.`CategoryID`,
       `a`.`Country`,
       `a`.`LocalName`,
       if((`a`.`Type` = 'FreeText'
           AND a.IsHybrid = 'YES'), 'Hybrid', if(`a`.`Type` = 'FreeText'
           AND a.IsHybrid = 'NO', 'FreeText', a.Type)) AS TYPE,
       `a`.`IsActive`,
       `a`.`LastChangeDate`
FROM `ProCatCountry` AS `a`
INNER JOIN `ProCat` AS `b` ON a.CategoryID = b.CategoryID
ORDER BY FIELD(a.TYPE, 'Normal', 'Special', 'Structured'),TYPE ASC 
LIMIT 25

What I order by as the second field is the TYPE field which is calculated in the if clause. I added this because without using the second order field, there will be sorting problem, because the field a.TYPE is ENUM , so I have to fix the sort using a second order field.

But now I added the second field, I runs successfully and nicely when I use sql client like sqlyog, but when I use return $this->_myAdapter->fetchAll($select); to execute the sql, there come a TYPE is ambiguous error. I think the problem lies in the Zend Framework fetchAll() method, but how can I fix it?

Answer 1

You can't use TYPE as an ORDER BY Parameter because it is an only an ALIAS of your IF statement. You can make TYPE as an ORDER BY Parameter if it is in a sub-query. See my example below:

 SELECT * FROM(
    SELECT `a`.`ChannelID`,
           `a`.`CategoryID`,
           `a`.`Country`,
           `a`.`LocalName`,
           if((`a`.`Type` = 'FreeText'
               AND a.IsHybrid = 'YES'), 'Hybrid', if(`a`.`Type` = 'FreeText'
               AND a.IsHybrid = 'NO', 'FreeText', a.Type)) AS TYPE,
           `a`.`IsActive`,
           `a`.`LastChangeDate`
    FROM `ProCatCountry` AS `a`
    INNER JOIN `ProCat` AS `b` ON a.CategoryID = b.CategoryID
    ORDER BY FIELD(a.TYPE, 'Normal', 'Special', 'Structured') ASC 
    LIMIT 25) AS A ORDER BY TYPE ASC