Question

In my symfony 1.4 project I have query with two joins to the same table (different foreign keys):

return ArticleQuery::create(null,$criteria)
        ->joinWithArticleCategoryRelatedByNewsCategoryId()
        ->joinWithArticleCategoryRelatedByHelpCategoryId();

I’m getting error:
SQLSTATE[42000]: Syntax error or access violation: 1066 Not unique table/alias: ‘article_category’

How can I add alias to this join?

Answer 1

Note: I use Propel 1.6

It should be enough to pass an argument to the join method.

return ArticleQuery::create(null,$criteria)
        ->joinWithArticleCategoryRelatedByNewsCategoryId('news')
        ->joinWithArticleCategoryRelatedByHelpCategoryId('help');

Look in your generated BaseArticleQuery.php to see what methods have been generated for you. One of my join methods look like this:

/**
 * Adds a JOIN clause to the query using the ArticleKeyword relation
 *
 * @param     string $relationAlias optional alias for the relation
 * @param     string $joinType Accepted values are null, 'left join', 'right join', 'inner join'
 *
 * @return    KeywordQuery The current query, for fluid interface
 */
public function joinArticleKeyword($relationAlias = null, $joinType = Criteria::LEFT_JOIN)

One of the strengths of Propel, is that nearly everything has a concrete method. So if you have an IDE with support for code completion, you can receive hints of what arguments the methods support.