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The DBQuery class

The DBQuery class is a query builder which helps you create SQL queries. For instance:

$sql = new DbQuery();
$sql->select('*');
$sql->from('cms', 'c');
$sql->innerJoin('cms_lang', 'l', 'c.id_cms = l.id_cms AND l.id_lang = '.(int)$id_lang);
$sql->where('c.active = 1');
$sql->orderBy('position');
return Db::getInstance()->executeS($sql);

Main methods

__toString(): Generate and get the query.
build(): Generate and get the query (return a string).
from(string $table, mixed $alias = null): Set table for FROM clause.
groupBy(string $fields): Add a GROUP BY restriction.
having(string $restriction): Add a restriction in the HAVING clause (each restriction will be separated by an AND statement).
innerJoin(string $table, string $alias = null, string $on = null): Add a INNER JOIN clause
E.g. $this->innerJoin('product p ON ...').
join(string $join): Add a JOIN clause
E.g. $this->join('RIGHT JOIN'.DB_PREFIX.'produc t p ON ...');.
leftJoin(string $table, string $alias = null, string $on = null): Add a LEFT JOIN clause.
leftOuterJoin(string $table, string $alias = null, string $on = null): Add a LEFT OUTER JOIN clause.
limit(int $limit, int $offset = 0): Limit results in query.
naturalJoin(string $table, string $alias = null): Add a NATURAL JOIN clause.
orderBy(string $fields): Add an ORDER BY restriction.
select(string $fields): Add fields in query selection.
where(string $restriction): Add a restriction in WHERE clause (each restriction will be separated by an AND statement).