/*
* Copyright 2004-2014 H2 Group. Multiple-Licensed under the MPL 2.0,
* and the EPL 1.0 (http://h2database.com/html/license.html).
* Initial Developer: H2 Group
*/
package org.h2.mvstore.db;
import java.util.Arrays;
import java.util.Collections;
import java.util.HashSet;
import java.util.Iterator;
import java.util.List;
import java.util.Map.Entry;
import java.util.concurrent.atomic.AtomicLong;
import org.h2.api.ErrorCode;
import org.h2.engine.Database;
import org.h2.engine.Session;
import org.h2.index.BaseIndex;
import org.h2.index.Cursor;
import org.h2.index.IndexType;
import org.h2.message.DbException;
import org.h2.mvstore.DataUtils;
import org.h2.mvstore.db.TransactionStore.Transaction;
import org.h2.mvstore.db.TransactionStore.TransactionMap;
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.TableFilter;
import org.h2.value.Value;
import org.h2.value.ValueArray;
import org.h2.value.ValueLong;
import org.h2.value.ValueNull;
/**
* A table stored in a MVStore.
*/
public class MVPrimaryIndex extends BaseIndex {
/**
* The minimum long value.
*/
static final ValueLong MIN = ValueLong.get(Long.MIN_VALUE);
/**
* The maximum long value.
*/
static final ValueLong MAX = ValueLong.get(Long.MAX_VALUE);
/**
* The zero long value.
*/
static final ValueLong ZERO = ValueLong.get(0);
private final MVTable mvTable;
private final String mapName;
private TransactionMap<Value, Value> dataMap;
private final AtomicLong lastKey = new AtomicLong(0);
private int mainIndexColumn = -1;
public MVPrimaryIndex(Database db, MVTable table, int id,
IndexColumn[] columns, IndexType indexType) {
this.mvTable = table;
initBaseIndex(table, id, table.getName() + "_DATA", columns, indexType);
int[] sortTypes = new int[columns.length];
for (int i = 0; i < columns.length; i++) {
sortTypes[i] = SortOrder.ASCENDING;
}
ValueDataType keyType = new ValueDataType(null, null, null);
ValueDataType valueType = new ValueDataType(db.getCompareMode(), db,
sortTypes);
mapName = "table." + getId();
Transaction t = mvTable.getTransaction(null);
dataMap = t.openMap(mapName, keyType, valueType);
t.commit();
if (!table.isPersistData()) {
dataMap.map.setVolatile(true);
}
Value k = dataMap.lastKey();
lastKey.set(k == null ? 0 : k.getLong());
}
@Override
public String getCreateSQL() {
return null;
}
@Override
public String getPlanSQL() {
return table.getSQL() + ".tableScan";
}
public void setMainIndexColumn(int mainIndexColumn) {
this.mainIndexColumn = mainIndexColumn;
}
public int getMainIndexColumn() {
return mainIndexColumn;
}
@Override
public void close(Session session) {
// ok
}
@Override
public void add(Session session, Row row) {
if (mainIndexColumn == -1) {
if (row.getKey() == 0) {
row.setKey(lastKey.incrementAndGet());
}
} else {
long c = row.getValue(mainIndexColumn).getLong();
row.setKey(c);
}
if (mvTable.getContainsLargeObject()) {
for (int i = 0, len = row.getColumnCount(); i < len; i++) {
Value v = row.getValue(i);
Value v2 = v.copy(database, getId());
if (v2.isLinkedToTable()) {
session.removeAtCommitStop(v2);
}
if (v != v2) {
row.setValue(i, v2);
}
}
}
TransactionMap<Value, Value> map = getMap(session);
Value key = ValueLong.get(row.getKey());
Value old = map.getLatest(key);
if (old != null) {
String sql = "PRIMARY KEY ON " + table.getSQL();
if (mainIndexColumn >= 0 && mainIndexColumn < indexColumns.length) {
sql += "(" + indexColumns[mainIndexColumn].getSQL() + ")";
}
DbException e = DbException.get(ErrorCode.DUPLICATE_KEY_1, sql);
e.setSource(this);
throw e;
}
try {
map.put(key, ValueArray.get(row.getValueList()));
} catch (IllegalStateException e) {
throw mvTable.convertException(e);
}
// because it's possible to directly update the key using the _rowid_
// syntax
if (row.getKey() > lastKey.get()) {
lastKey.set(row.getKey());
}
}
@Override
public void remove(Session session, Row row) {
if (mvTable.getContainsLargeObject()) {
for (int i = 0, len = row.getColumnCount(); i < len; i++) {
Value v = row.getValue(i);
if (v.isLinkedToTable()) {
session.removeAtCommit(v);
}
}
}
TransactionMap<Value, Value> map = getMap(session);
try {
Value old = map.remove(ValueLong.get(row.getKey()));
if (old == null) {
throw DbException.get(ErrorCode.ROW_NOT_FOUND_WHEN_DELETING_1,
getSQL() + ": " + row.getKey());
}
} catch (IllegalStateException e) {
throw mvTable.convertException(e);
}
}
@Override
public Cursor find(Session session, SearchRow first, SearchRow last) {
ValueLong min, max;
if (first == null) {
min = MIN;
} else if (mainIndexColumn < 0) {
min = ValueLong.get(first.getKey());
} else {
ValueLong v = (ValueLong) first.getValue(mainIndexColumn);
if (v == null) {
min = ValueLong.get(first.getKey());
} else {
min = v;
}
}
if (last == null) {
max = MAX;
} else if (mainIndexColumn < 0) {
max = ValueLong.get(last.getKey());
} else {
ValueLong v = (ValueLong) last.getValue(mainIndexColumn);
if (v == null) {
max = ValueLong.get(last.getKey());
} else {
max = v;
}
}
TransactionMap<Value, Value> map = getMap(session);
return new MVStoreCursor(session, map.entryIterator(min), max);
}
@Override
public MVTable getTable() {
return mvTable;
}
@Override
public Row getRow(Session session, long key) {
TransactionMap<Value, Value> map = getMap(session);
Value v = map.get(ValueLong.get(key));
if (v == null) {
throw DbException.get(ErrorCode.ROW_NOT_FOUND_IN_PRIMARY_INDEX,
getSQL() + ": " + key);
}
ValueArray array = (ValueArray) v;
Row row = session.createRow(array.getList(), 0);
row.setKey(key);
return row;
}
@Override
public double getCost(Session session, int[] masks,
TableFilter[] filters, int filter, SortOrder sortOrder,
HashSet<Column> allColumnsSet) {
try {
//<<<<<<< HEAD
// //COST_ROW_OFFSET是1000，避免dataMap.sizeAsLongMax()为0时得到cost=0(代价最小)，从而错误选择索引
// long cost = 10 * (dataMap.sizeAsLongMax() + Constants.COST_ROW_OFFSET);
// return cost;
//=======
return 10 * getCostRangeIndex(masks, dataMap.sizeAsLongMax(),
filters, filter, sortOrder, true, allColumnsSet);
} catch (IllegalStateException e) {
throw DbException.get(ErrorCode.OBJECT_CLOSED, e);
}
}
@Override
public int getColumnIndex(Column col) {
// can not use this index - use the delegate index instead
return -1;
}
@Override
public void remove(Session session) { //对应drop table
TransactionMap<Value, Value> map = getMap(session);
if (!map.isClosed()) {
Transaction t = mvTable.getTransaction(session);
t.removeMap(map);
}
}
@Override
public void truncate(Session session) { //对应truncate table，只清空记录，不清元数据
TransactionMap<Value, Value> map = getMap(session);
if (mvTable.getContainsLargeObject()) {
database.getLobStorage().removeAllForTable(table.getId());
}
map.clear();
}
@Override
public boolean canGetFirstOrLast() {
return true;
}
@Override
public Cursor findFirstOrLast(Session session, boolean first) { //用于快束min、max聚合查询，只有建立了PRIMARY KEY才有用
TransactionMap<Value, Value> map = getMap(session);
ValueLong v = (ValueLong) (first ? map.firstKey() : map.lastKey());
if (v == null) {
return new MVStoreCursor(session, Collections
.<Entry<Value, Value>> emptyList().iterator(), null);
}
Value value = map.get(v);
Entry<Value, Value> e = new DataUtils.MapEntry<Value, Value>(v, value);
List<Entry<Value, Value>> list = Arrays.asList(e);
MVStoreCursor c = new MVStoreCursor(session, list.iterator(), v);
c.next();
return c;
}
@Override
public boolean needRebuild() {
return false;
}
@Override
public long getRowCount(Session session) {
TransactionMap<Value, Value> map = getMap(session);
return map.sizeAsLong();
}
/**
* The maximum number of rows, including uncommitted rows of any session.
*
* @return the maximum number of rows
*/
public long getRowCountMax() {
try {
return dataMap.sizeAsLongMax();
} catch (IllegalStateException e) {
throw DbException.get(ErrorCode.OBJECT_CLOSED, e);
}
}
@Override
public long getRowCountApproximation() {
return getRowCountMax();
}
@Override
public long getDiskSpaceUsed() {
// TODO estimate disk space usage
return 0;
}
public String getMapName() {
return mapName;
}
@Override
public void checkRename() {
// ok
}
/**
* Get the key from the row.
*
* @param row the row
* @param ifEmpty the value to use if the row is empty
* @param ifNull the value to use if the column is NULL
* @return the key
*/
ValueLong getKey(SearchRow row, ValueLong ifEmpty, ValueLong ifNull) {
if (row == null) {
return ifEmpty;
}
Value v = row.getValue(mainIndexColumn);
if (v == null) {
throw DbException.throwInternalError(row.toString());
} else if (v == ValueNull.INSTANCE) {
return ifNull;
}
return (ValueLong) v.convertTo(Value.LONG);
}
/**
* Search for a specific row or a set of rows.
*
* @param session the session
* @param first the key of the first row
* @param last the key of the last row
* @return the cursor
*/
Cursor find(Session session, ValueLong first, ValueLong last) {
TransactionMap<Value, Value> map = getMap(session);
return new MVStoreCursor(session, map.entryIterator(first), last);
}
@Override
public boolean isRowIdIndex() {
return true;
}
/**
* Get the map to store the data.
*
* @param session the session
* @return the map
*/
TransactionMap<Value, Value> getMap(Session session) {
if (session == null) {
return dataMap;
}
Transaction t = mvTable.getTransaction(session);
return dataMap.getInstance(t, Long.MAX_VALUE);
}
/**
* A cursor.
*/
class MVStoreCursor implements Cursor {
private final Session session;
private final Iterator<Entry<Value, Value>> it;
private final ValueLong last;
private Entry<Value, Value> current;
private Row row;
public MVStoreCursor(Session session, Iterator<Entry<Value, Value>> it, ValueLong last) {
this.session = session;
this.it = it;
this.last = last;
}
@Override
public Row get() {
if (row == null) {
if (current != null) {
ValueArray array = (ValueArray) current.getValue();
row = session.createRow(array.getList(), 0);
row.setKey(current.getKey().getLong());
}
}
return row;
}
@Override
public SearchRow getSearchRow() {
return get();
}
@Override
public boolean next() {
current = it.hasNext() ? it.next() : null;
if (current != null && current.getKey().getLong() > last.getLong()) {
current = null;
}
row = null;
return current != null;
}
@Override
public boolean previous() {
throw DbException.getUnsupportedException("previous");
}
}
}