How to use DISTINCT here in my CODEIGNITER request

Question

$q = $this->db->select(' books.title, reserved_books.id, reserved_books.isbn, reserved_books.price, reserved_books.item_sold, reserved_books.date_sold, reserved_books.total_amount ') ->from('reserved_books') ->join('books','reserved_books.isbn= books.isbn') ->limit($limit,$offset); 

How can I use here separately in my request? reserved_books.isbn is unique.

Answer 1

Try below:

 $this->db->distinct(); 

but Distinct will not always work. You must add - >group_by("name_of_the_column_which_needs_to_be unique");

 $this->db->group_by('column_name'); 

Answer 2

Adds the keyword "DISTINCT" to the query before selecting

 $this->db->distinct(); 

Renouncement

Answer 3

Here is how to do it

 $select = array( 'books.title', 'reserved_books.id', 'DISTINCT reserved_books.isbn', 'reserved_books.price', 'reserved_books.item_sold', 'reserved_books.date_sold', 'reserved_books.total_amount' ); $q = $this->db ->select($select) ->from('reserved_books') ->join('books','reserved_books.isbn= books.isbn') ->group_by('reserved_books.isbn') ->limit($limit,$offset); 

Answer 4

You do not need a connection

  $query=$this->db->distinct()->select('table_attribute')->where('condition')->get('table_name'); return $query->result(); 

Answer 5

Here is the best way to delete a duplicate entry.

 $query = $this->db->select("inf.id, inf.sku, inf.fab_id, inf.sku, inf.amount, inf.min_length, inf.num_of_pieces, inf.width ,inf.type") ->join("retailcat","retailcat.sku=SUBSTRING(inf.sku,1,19) AND retailcat.category=218","INNER") ->distinct() ->get("input_factor inf");