Union Select Method

The union_select method select column from create Union Query Builder with its aliases.

Basic Usage

Here is the basic usage union_select method from $db property on SENE_Model class.

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$this->db->union_select(string $col_name, string $alias): $this->db

Parameters

Update method has 2 required parameters and 1 optional parameter.

$col_name

The $col_name value can be a single column name or can be filled with wildcard "*", or can be filled with MySQL function.

$alias

The $alias value can be a string that represent the selected column.

Example

For the example we assumed want to select a colum in a table with union_select method.

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<?php
class Blog_Model extends SENE_Model{
  public $table = 'd_blog';
  public $table_alias = 'b';

  public function __construct(){
    parent::__construct();
    $this->db->from($this->table,$this->table_alias);
  }
  public function searchByScore($keyword){
    $this->db->union_flush();

    //1st union
    $this->db->select('id');
    $this->db->select('title');
    $this->db->select('excerpt');
    $this->db->select('date_modified');
    $this->db->select_as("3",'score');
    $this->db->from($this->table,$this->table_alias);
    $this->db->where('title',$keyword,'or','like',1,0);
    $this->db->where('excerpt',$keyword,'or','like',0,1);
    $this->db->union_create();

    //2nd union
    $this->db->select('id');
    $this->db->select('title');
    $this->db->select('excerpt');
    $this->db->select('date_modified');
    $this->db->select_as("2",'score');
    $this->db->from($this->table,$this->table_alias);
    $this->db->where('title',$keyword,'or','like%',1,0);
    $this->db->where('excerpt',$keyword,'or','like%',0,1);
    $this->db->union_create();

    //3rd union
    $this->db->select('id');
    $this->db->select('title');
    $this->db->select('excerpt');
    $this->db->select('date_modified');
    $this->db->select_as("1",'score');
    $this->db->from($this->table,$this->table_alias);
    $this->db->where('title',$keyword,'or','%like',1,0);
    $this->db->where('excerpt',$keyword,'or','%like',0,1);
    $this->db->union_create();

    //4th union
    $this->db->select('id');
    $this->db->select('title');
    $this->db->select('excerpt');
    $this->db->select('date_modified');
    $this->db->select_as("0",'score');
    $this->db->from($this->table,$this->table_alias);
    $this->db->where('title',$keyword,'or','%like%',1,0);
    $this->db->where('excerpt',$keyword,'or','%like%',0,1);
    $this->db->union_create();

    $this->db->union_select('id,title,date_modified,score','score');
    $this->db->union_group_by('id');
    $this->db->union_order_by('score','desc')->union_limit(1, 14);
    return $this->db->union_get();
  }
}
Union Get Method
Update AS Method