SQL query to match a comma-separated string against a comma-separated string?

Question

The MySQL query below uses PHP to pull in the $sector, which is a single digit, and the $subsector_text, which is a comma separated string. The $subsector_text could be a

Answer 1

Your approach is correct, but need some modifications. Instead of try to match in only one condition (REGEXP), can create multiple conditions joined with OR...

Example:

$subsectorArray = explode(',', $subsector_text);
$or = [];
foreach ($subsectorArray as $subsector){
    $or[] = "a.subsector REGEXP '[^[:alnum:]]{$subsector}[^[:alnum:]]|^{$subsector}[^[:alnum:]]|[^[:alnum:]]{$subsector}$|^{$subsector}$'";
}
$orStr = implode(' OR ', $or);

 $sql = "
SELECT DISTINCT a.id
              , a.name
              , a.category_id
              , a.sector
              , a.subsector
              , a.year_in_operation
              , a.state
              , a.total_value
              , b.country_id
              , b.project_id
              , c.isocode_3
              , c.name
           FROM com_barchan_project a
           JOIN com_barchan_location b
             ON b.project_id = a.id
           JOIN com_barchan_country c
             ON c.id = b.country_id
           JOIN com_barchan_project_value_join d
             ON a.id = d.project_id
          WHERE a.state = 1 
            AND a.sector = '$sector'
            AND ($orStr)
          ORDER 
             BY a.total_value DESC
              , a.category_id ASC
              , a.name ASC
";