php codeigniter选择查询

Question

This is the my original SQL query

select 'car' as type,id,title,status from car_product
union
select 'van' as type,id,title,status from van_product

Now I want to run this query using CodeIgniter, so I try to use this one

$this -> db -> select('`car` As type,id,title,status');
$this -> db -> from('car_product');
$this -> db -> where('status =',$status);
$query_car = $this -> db -> get()->result();

$this -> db -> select('`van` As type,id,title,status');
$this -> db -> from('van_product');
$this -> db -> where('status =',$status);
$query_van = $this -> db -> get()->result();

return array_merge($query_car, $query_van);

but it's not working, please can you help?

Answer 1

You can use ->query() method directly without using queryBuilder for this.

$query = $this->db->query("select 'car' as type,id,title,status from car_product union    select 'van' as type,id,title,status from van_product");

Then you can deal it as you deal with your other queries

eg:

return $query->result();

Answer 2

if you want to do it the active record way, use this one.

 $this -> db -> select('"car" type,id,title,status',false);
 $this -> db -> from('car_product');
 $this -> db -> where('status =',$status);
 $query_car = $this -> db -> get()->result();

 $this -> db -> select('"van" type,id,title,status',false);
 $this -> db -> from('van_product');
 $this -> db -> where('status =',$status);
 $query_van = $this -> db -> get()->result();

 return array_merge($query_car, $query_van);

https://ellislab.com/codeigniter/user-guide/database/active_record.html

$this->db->select(); has an optional second parameter that enables you to use compound select statement when needed.

Note: you will not be protected against backticks when you set the optional parameter to "false"

Answer 3

Try removing '=', :

ex: $status = 'Chamara'

 $this->db->where("status",$status); 

//Produces: WHERE 'status' = 'Chamara'

Suggest: You can use arrays. Maybe in future you'll need to set more than one condition

 $condition = array("status"=>$status); $this->db->where($condition); 

Suggest 2: Use $this->db->get('van_product'); instead of

 $this -> db -> from('van_product'); $query_van = $this -> db -> get()->result(); 

// Produces: SELECT * FROM van_product