public function getSql()
    {
        if ($this->constraint instanceof ForeignKey) {
            return sprintf('ALTER TABLE %s ADD CONSTRAINT %s FOREIGN KEY (%s) REFERENCES %s (%s) MATCH SIMPLE ON UPDATE %s ON DELETE %s;'
                , $this->constraint->getTable()->getQualifiedName()
                , $this->constraint->getName()
                , implode(',', $this->constraint->getColumns())
                , $this->constraint->getReferencedTable()->getQualifiedName()
                , implode(',', $this->constraint->getReferencedColumns())
                , $this->constraint->getUpdateAction()
                , $this->constraint->getDeleteAction()
            );
        }
        if ($this->constraint instanceof Unique) {
            return sprintf('ALTER TABLE %s ADD CONSTRAINT %s UNIQUE (%s);'
                , $this->constraint->getTable()->getQualifiedName()
                , $this->constraint->getName()
                , implode(',', $this->constraint->getColumns())
            );
        }
    }
public function getSql()
    {
        if ($this->constraint instanceof ForeignKey) {
            return sprintf('ALTER TABLE %s ADD CONSTRAINT %s FOREIGN KEY (%s) REFERENCES %s (%s) MATCH SIMPLE ON UPDATE %s ON DELETE %s;'
                , $this->constraint->getTable()->getQualifiedName()
                , $this->constraint->getName()
                , implode(',', $this->constraint->getColumns())
                , $this->constraint->getReferencedTable()->getQualifiedName()
                , implode(',', $this->constraint->getReferencedColumns())
                , $this->constraint->getUpdateAction()
                , $this->constraint->getDeleteAction()
            );
        }
        if ($this->constraint instanceof Unique) {
            return sprintf('ALTER TABLE %s ADD CONSTRAINT %s UNIQUE (%s);'
                , $this->constraint->getTable()->getQualifiedName()
                , $this->constraint->getName()
                , implode(',', $this->constraint->getColumns())
            );
        }
    }
{@inheritdoc}