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mysql - Codeigniter parentheses in dynamic Active Record query

I'm producing a query like the following using ActiveRecord

SELECT * FROM (`foods`) WHERE `type` = 'fruits' AND 
       `tags` LIKE '%green%' OR `tags` LIKE '%blue%' OR `tags` LIKE '%red%'

The number of tags and values is unknown. Arrays are created dynamically. Below I added a possible array.

$tags = array (                 
        '0'     => 'green'.
        '1'     => 'blue',
        '2'     => 'red'
);  

Having an array of tags, I use the following loop to create the query I posted on top.

$this->db->where('type', $type); //var type is retrieved from input value

foreach($tags as $tag):         
     $this->db->or_like('tags', $tag);
endforeach; 

The issue: I need to add parentheses around the LIKE clauses like below:

SELECT * FROM (`foods`) WHERE `type` = 'fruits' AND 
      (`tags` LIKE '%green%' OR `tags` LIKE '%blue%' OR `tags` LIKE '%red%')

I know how to accomplish this if the content within the parentheses was static but the foreach loop throws me off..

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1 Answer

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From the CI wiki:

The codeignighter ActiveRecord feature allows you to create SQL queries relatively simply and database-independant, however there isno specific support for including parenthesis in an SQL query.

For example when you want a where statement to come out simmilarly to the folowing:

WHERE (field1 = value || field2 = value) AND (field3 = value2 || field4 = value2) 

This can be worked around by feeding a string to the CI->db->where() function, in this case you will want to specifically escape your values.

See the following example:

$value=$this->db->escape($value);
$value2=$this->db->escape($value2);
$this->db->from('sometable');
$this->db->where("($field = $value || $field2 = $value)");
$this->db->where("($field3 = $value2 || $field4 = $value2)");
$this->db->get(); 

A simmilar workaround can be used for LIKE clauses:

$this->db->where("($field LIKE '%$value%' || $field2 LIKE '%$value%')");
$this->db->where("($field3 LIKE '%$value2%' || $field4 LIKE '%$value2%')"); 

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