Join Query in magento 2

Question

The below code entry is already in DB, Now I need to add one field to customer id and want to rerun this code via programmatically.

$this->getSelect()->join(
                    ['detail' => $this->getReviewDetailTable()], 'main_table.review_id = detail.review_id', ['detail_id', 'title', 'detail', 'nickname', 'customer_id']
            );

I have created a custom module from for Product Review. In above I have overrides the Magento review collection class, while overriding this part shows error as

You cannot define a correlation name 'detail' more than once

So Now In my override class I have added the one more field, But DB has the entry already. I also need to handle this while updating or overriding in my class so pls provide me a solution

Answer 1

Check below query

$this->getSelect()->join(
                    ['details' => $this->getReviewDetailTable()], 'main_table.review_id = details.review_id', ['detail_id', 'title', 'detail', 'nickname', 'customer_id']
            );

Answer 2

I know this question has an accepted answer but in this case the line parent::_iniselect() is doing reference to

\Magento\Review\Model\ResourceModel\Review\Collection

(the new parent) which extends from:

\Magento\Framework\Model\ResourceModel\Db\Collection\AbstractCollection

(the original parent) so you should change it for

\Magento\Framework\Model\ResourceModel\Db\Collection\AbstractCollection::_initSelect();

as shown below:

protected function _initSelect()
{
    //parent::_initSelect();
    \Magento\Framework\Model\ResourceModel\Db\Collection\AbstractCollection::_initSelect();

    $this->getSelect()->join(
        ['detail' => $this->getReviewDetailTable()],
        'main_table.review_id = detail.review_id',
        ['detail_id', 'title', 'detail', 'nickname', 'customer_id']
    );
}

Answer 3

What is happening is that your join is already set. What you could is to check whether the join was already set or not.

Something like this:

try {
    $this->getSelect()->join(
        ['details' => $this->getReviewDetailTable()], 'main_table.review_id = details.review_id',
        ['detail_id', 'title', 'detail', 'nickname', 'customer_id']
    );
} catch (\Exception $e) {
 ...
}

I would change the alias details to something more unique.

Answer 4

I tried this solution of yours but am getting an error where it says protectedMethod _initSelect cannot be accessed in public. I am trying to write my stuff after the _initSelect in Magento\SalesRule\Model\ResourceModel\Rule\Collection using after_initSelect. Got any advice?