func (s SchemaState) String() string {
	switch s {
	case StateDeleteOnly:
		return "delete only"
	case StateWriteOnly:
		return "write only"
	case StateWriteReorganization:
		return "write reorganization"
	case StateDeleteReorganization:
		return "delete reorganization"
	case StatePublic:
		return "public"
	default:
		return "none"
	}
}
String implements fmt.Stringer interface.
package model
import (
	"encoding/json"
	"strings"
	"time"
	"github.com/pingcap/errors"
	"github.com/pingcap/parser/mysql"
	"github.com/pingcap/parser/types"
	"github.com/pingcap/tipb/go-tipb"
)
type SchemaState byte
const (
	StateNone SchemaState = iota
	StateDeleteOnly
	StateWriteOnly
	StateWriteReorganization
	StateDeleteReorganization
	StatePublic
)