Codeigniter如何删除子查询中的“`”

Question

I have a problem when I run sub-query in from clause.
Here is my code

$subquery = "select column1, column2 from table limit 10, 10"
$this->db->select(column1, false)->from("( $subquery ) as b");
$this->db->get();

I get database error "Undeclared variable: 10" And print my query is:

select column1 from ((select column1, column2 from table limit 10, `10` ) as b)

How can I remove this character "`"

Answer 1

You can use $this->db->_protect_identifiers=false; which will remove all backticks on this query.

So your query will be something like:

$subquery = "select column1, column2 from table limit 10, 10"
$this->db->_protect_identifiers=false;
$this->db->select(column1, false)->from("( $subquery ) as b");
$this->db->_protect_identifiers=true;   // You can make it true again here to avoid removing of backtickes in further code unnecessarily 
$this->db->get();