ZF2 DB Adapter - Column not found: 1054 Unknown column - mysql

Question

I'm using ZF2 DB Adapter and get following error on my query:
Column not found: 1054 Unknown column '"product"'
But "product" is no column, it's a value, so how come?
This is how I build the query:
$select = $this->getGateway()->getSql()->select();
$select->join('keywordlink', 'keywordlink_ref_type = "product" AND keywordlink_ref_id = product_id', ['keyword_count' => new Expression('COUNT(keyword_id)')], Select::JOIN_LEFT);
$select->where(['product_deleted IS NULL']);
$select->group(['product_id']);
Btw, the field keywordlink_ref_id is an ENUM in the mysql database.
When I write the SQL myself it works:
SELECT
product.*, COUNT(DISTINCT keywordlink_keyword_id) AS keyword_count
FROM
adcheck.product
LEFT JOIN
keywordlink
ON
keywordlink_ref_type = "product" AND keywordlink_ref_id = product_id
WHERE
product_deleted IS NULL
GROUP BY
product_id
Thanks

Answer 1

Ok, I don't know why it didn't work as before but it works when I move the
keywordlink_ref_type = "product"
into the where condition:
SELECT
product.*, COUNT(DISTINCT keywordlink_keyword_id) AS keyword_count
FROM
adcheck.product
LEFT JOIN
keywordlink
ON
keywordlink_ref_id = product_id
WHERE
keywordlink_ref_type = "product" AND product_deleted IS NULL
GROUP BY
product_id

Answer 2

$sql = $this->getGateway()->getSql()->select();
$sql->from('product')->join('keywordlink', "keywordlink.ref_id" = "product.id", LEFT);
$sql->where->equalTo( 'keywordlink.column' = 'product.column');
$sql->where->equalTo('product.deleted', NULL);
$sql->group('product.product_id');
The column wasn't found because not pointing table in your query.The solution something like this,but for proper syntax of ZF2 query builder you should also check out this zend2 link: http://framework.zend.com/manual/1.12/en/zend.db.select.html