lib/Doctrine/DBAL/Platforms/SQLServerPlatform.php
private function _appendUniqueConstraintDefinition($sql, Index $index)
    {
        $fields = [];

        foreach ($index->getQuotedColumns($this) as $field) {
            $fields[] = $field . ' IS NOT NULL';
        }

        return $sql . ' WHERE ' . implode(' AND ', $fields);
    }
private function _appendUniqueConstraintDefinition($sql, Index $index)
    {
        $fields = [];

        foreach ($index->getQuotedColumns($this) as $field) {
            $fields[] = $field . ' IS NOT NULL';
        }

        return $sql . ' WHERE ' . implode(' AND ', $fields);
    }
private function _appendUniqueConstraintDefinition ( $ sql , Index $ index ) { $ fields = [ ] ; foreach ( $ index -> getQuotedColumns ( $ this ) as $ field ) { $ fields [ ] = $ field . ' IS NOT NULL' ; } return $ sql . ' WHERE ' . implode ( ' AND ' , $ fields ) ; }
Extend unique key constraint with required filters

@param string $sql

@return string
Extend unique key constraint with required filters