func (p *QueryProcess) WithChildren(children ...sql.Node) (sql.Node, error) {
	if len(children) != 1 {
		return nil, sql.ErrInvalidChildrenNumber.New(p, len(children), 1)
	}
	return NewQueryProcess(children[0], p.Notify), nil
}
WithChildren implements the Node interface.
package plan
import (
	"io"
	"github.com/src-d/go-mysql-server/sql"
)
type QueryProcess struct {
	UnaryNode
	Notify NotifyFunc
}
type NotifyFunc func()
func NewQueryProcess(node sql.Node, notify NotifyFunc) *QueryProcess {
	return &QueryProcess{UnaryNode{Child: node}, notify}
}