public IndexOptionToggle(Identifier key, ToggleToken value): base(key) {
			Debug.Assert(value != null);
			this.value = value.On;
		}
		public SetIdentityInsertStatement(Qualified<SchemaName, TableName> tableName, ToggleToken toggle) {
			Debug.Assert(tableName != null);
			Debug.Assert(toggle != null);
			this.tableName = tableName;
			enabled = toggle.On;
		}