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copied!<p>It turns out you can't. At least not with the syntax provided above and not with CakePHP 1.2.6. I went over the source (yay! to open source frameworks!) and found the file <code>cake/libs/model/datasources/dbo_source.php</code> which contains the code for the joins.</p> <p>It all starts with <code>DboSource::renderStatement()</code> which does a shallow walk of the <code>$query['joins']</code> array, replacing those join definitions with SQL fragments via <code>DboSource::buildJoinStatement($join)</code>, which does some tidying up of the arguments (filling in blanks etc.) and then calls <code>DboSource::renderJoinStatement</code> to create the SQL fragment of a single join clause.</p> <blockquote> <p><em>me:</em> That should be easy to fix!</p> </blockquote> <p>I was told not to edit stuff in <code>cake/libs</code>, so instead I copied the file <code>dbo_source.php</code> to <code>app/models/datasources/</code> for editing. Then I took my axe and refactored the shallow walk of the <code>$query['joins']</code> array in <code>DboSource::renderStatement()</code> into a new method <code>DboSource::buildJoinStatementArray()</code> resulting in these two methods:</p> <pre><code>function buildStatement($query, $model) { $query = array_merge(array('offset' => null, 'joins' => array()), $query); # refactored (extract method) to make recursion easier $query['joins'] = $this->buildJoinStatementArray($query['joins']); return $this->renderStatement('select', array( 'conditions' => $this->conditions($query['conditions'], true, true, $model), 'fields' => implode(', ', $query['fields']), 'table' => $query['table'], 'alias' => $this->alias . $this->name($query['alias']), 'order' => $this->order($query['order']), 'limit' => $this->limit($query['limit'], $query['offset']), 'joins' => implode(' ', $query['joins']), 'group' => $this->group($query['group']) )); } /** * Replaces the join statement array syntax with SQL join clauses. */ function buildJoinStatementArray($joins) { if (!empty($joins)) { $count = count($joins); for ($i = 0; $i < $count; $i++) { if (is_array($joins[$i])) { $joins[$i] = $this->buildJoinStatement($joins[$i]); # $joins[$i] now contains something like "LEFT JOIN users As User on User.group_id = Group.id" } } } return $joins; } </code></pre> <p>Once I had <code>DboSource::buildJoinStatementArray()</code>, it was time to change <code>DboSource::buildJoinStatement()</code> - all I did was added a check for <code>$data['joins']</code> and an alternative rendering method for that case:</p> <pre><code>function buildJoinStatement($join) { $data = array_merge(array( 'type' => null, 'alias' => null, 'table' => 'join_table', 'conditions' => array() ), $join); if (!empty($data['alias'])) { $data['alias'] = $this->alias . $this->name($data['alias']); } if (!empty($data['conditions'])) { $data['conditions'] = trim($this->conditions($data['conditions'], true, false)); } # allow for nested joins if (!empty($data['joins']) and is_array($data['joins'])) { $data['joins'] = $this->buildJoinStatementArray($data['joins']); return $this->renderNestedJoinStatement($data); } else { return $this->renderJoinStatement($data); } } </code></pre> <p>The new <code>renderNestedJoinStatement()</code> method is pretty similar to <code>DboSource::renderJoinStatement()</code>:</p> <pre><code>/** * Renders a final SQL JOIN that contains nested join statements * * @param array $data * @return string */ function renderNestedJoinStatement($data) { extract($data); $nestedJoins = implode(' ', $joins); return trim("{$type} JOIN ({$table} {$alias} {$nestedJoins})ON ({$conditions})"); } </code></pre>

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