/*
* Copyright 2004-2023 H2 Group. Multiple-Licensed under the MPL 2.0,
* and the EPL 1.0 (https://h2database.com/html/license.html).
* Initial Developer: H2 Group
*/
package org.h2.result;
import java.util.Collection;
import org.h2.value.Value;
/**
* This interface is used to extend the LocalResult class, if data does not fit
* in memory.
*/
public interface ResultExternal {
/**
* Reset the current position of this object.
*/
void reset();
/**
* Get the next row from the result.
*
* @return the next row or null
*/
Value[] next();
/**
* Add a row to this object.
*
* @param values the row to add
* @return the new number of rows in this object
*/
int addRow(Value[] values);
/**
* Add a number of rows to the result.
*
* @param rows the list of rows to add
* @return the new number of rows in this object
*/
int addRows(Collection<Value[]> rows);
/**
* Close this object and delete the temporary file.
*/
void close();
/**
* Remove the row with the given values from this object if such a row
* exists.
*
* @param values the row
* @return the new row count
*/
int removeRow(Value[] values);
/**
* Check if the given row exists in this object.
*
* @param values the row
* @return true if it exists
*/
boolean contains(Value[] values);
/**
* Create a shallow copy of this object if possible.
*
* @return the shallow copy, or null
*/
ResultExternal createShallowCopy();
}