package org.h2.index;
import java.util.ArrayList;
import org.h2.command.dml.AllColumnsForPlan;
import org.h2.engine.Session;
import org.h2.message.DbException;
import org.h2.result.Row;
import org.h2.result.SearchRow;
import org.h2.result.SortOrder;
import org.h2.table.Column;
import org.h2.table.IndexColumn;
import org.h2.table.MetaTable;
import org.h2.table.TableFilter;
public class MetaIndex extends BaseIndex {
private final MetaTable meta;
private final boolean scan;
public MetaIndex(MetaTable meta, IndexColumn[] columns, boolean scan) {
super(meta, 0, null, columns, IndexType.createNonUnique(true));
this.meta = meta;
this.scan = scan;
}
@Override
public void close(Session session) {
}
@Override
public void add(Session session, Row row) {
throw DbException.getUnsupportedException("META");
}
@Override
public void remove(Session session, Row row) {
throw DbException.getUnsupportedException("META");
}
@Override
public Cursor find(Session session, SearchRow first, SearchRow last) {
ArrayList<Row> rows = meta.generateRows(session, first, last);
return new MetaCursor(rows);
}
@Override
public double getCost(Session session, int[] masks,
TableFilter[] filters, int filter, SortOrder sortOrder,
AllColumnsForPlan allColumnsSet) {
if (scan) {
return 10 * MetaTable.ROW_COUNT_APPROXIMATION;
}
return getCostRangeIndex(masks, MetaTable.ROW_COUNT_APPROXIMATION,
filters, filter, sortOrder, false, allColumnsSet);
}
@Override
public void truncate(Session session) {
throw DbException.getUnsupportedException("META");
}
@Override
public void remove(Session session) {
throw DbException.getUnsupportedException("META");
}
@Override
public int getColumnIndex(Column col) {
if (scan) {
return -1;
}
return super.getColumnIndex(col);
}
@Override
public boolean isFirstColumn(Column column) {
if (scan) {
return false;
}
return super.isFirstColumn(column);
}
@Override
public void checkRename() {
throw DbException.getUnsupportedException("META");
}
@Override
public boolean needRebuild() {
return false;
}
@Override
public String getCreateSQL() {
return null;
}
@Override
public boolean canGetFirstOrLast() {
return false;
}
@Override
public Cursor findFirstOrLast(Session session, boolean first) {
throw DbException.getUnsupportedException("META");
}
@Override
public long getRowCount(Session session) {
return MetaTable.ROW_COUNT_APPROXIMATION;
}
@Override
public long getRowCountApproximation() {
return MetaTable.ROW_COUNT_APPROXIMATION;
}
@Override
public long getDiskSpaceUsed() {
return meta.getDiskSpaceUsed();
}
@Override
public String getPlanSQL() {
return "meta";
}
}