func (f Version) IsNullable() bool {
	return false
}
IsNullable implements the Expression interface.
package function
import (
	"fmt"
	"github.com/src-d/go-mysql-server/sql"
)
const mysqlVersion = "8.0.11"
type Version string
func NewVersion(versionPostfix string) func(...sql.Expression) (sql.Expression, error) {
	return func(...sql.Expression) (sql.Expression, error) {
		return Version(versionPostfix), nil
	}
}
func (f Version) Type() sql.Type { return sql.Text }