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提交 8cd9dc21 authored 作者: Thomas Mueller's avatar Thomas Mueller
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New experimental feature to speed up CREATE TABLE ... AS SELECT.

上级 36c23898
隐藏空白字符变更
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正在显示 包含 240 行增加 和 65 行删除
h2/src/main/org/h2/command/ddl/CreateTable.java
浏览文件 @ 8cd9dc21
......@@ -171,6 +171,7 @@ public class CreateTable extends SchemaCommand {
insert.setSortedInsertMode(sortedInsertMode);
insert.setQuery(asQuery);
insert.setTable(table);
insert.setInsertFromSelect(true);
insert.prepare();
insert.update();
} finally {
......
h2/src/main/org/h2/command/dml/Insert.java
浏览文件 @ 8cd9dc21
......@@ -21,6 +21,7 @@ import org.h2.expression.Parameter;
import org.h2.index.PageIndex;
import org.h2.message.DbException;
import org.h2.result.ResultInterface;
import org.h2.result.ResultTarget;
import org.h2.result.Row;
import org.h2.table.Column;
import org.h2.table.Table;
......@@ -32,13 +33,15 @@ import org.h2.value.Value;
* This class represents the statement
* INSERT
*/
public class Insert extends Prepared {
public class Insert extends Prepared implements ResultTarget {
private Table table;
private Column[] columns;
private ArrayList<Expression[]> list = New.arrayList();
private Query query;
private boolean sortedInsertMode;
private int rowNumber;
private boolean insertFromSelect;
public Insert(Session session) {
super(session);
......@@ -89,17 +92,18 @@ public class Insert extends Prepared {
}
private int insertRows() {
int count;
session.getUser().checkRight(table, Right.INSERT);
setCurrentRowNumber(0);
table.fire(session, Trigger.INSERT, true);
if (list.size() > 0) {
count = 0;
for (int x = 0; x < list.size(); x++) {
Expression[] expr = list.get(x);
rowNumber = 0;
int listSize = list.size();
if (listSize > 0) {
int columnLen = columns.length;
for (int x = 0; x < listSize; x++) {
Row newRow = table.getTemplateRow();
Expression[] expr = list.get(x);
setCurrentRowNumber(x + 1);
for (int i = 0; i < columns.length; i++) {
for (int i = 0; i < columnLen; i++) {
Column c = columns[i];
int index = c.getColumnId();
Expression e = expr[i];
......@@ -114,6 +118,7 @@ public class Insert extends Prepared {
}
}
}
rowNumber++;
table.validateConvertUpdateSequence(session, newRow);
boolean done = table.fireBeforeRow(session, null, newRow);
if (!done) {
......@@ -122,39 +127,44 @@ public class Insert extends Prepared {
session.log(table, UndoLogRecord.INSERT, newRow);
table.fireAfterRow(session, null, newRow, false);
}
count++;
}
} else {
ResultInterface rows = query.query(0);
count = 0;
table.lock(session, true, false);
while (rows.next()) {
count++;
Value[] r = rows.currentRow();
Row newRow = table.getTemplateRow();
setCurrentRowNumber(count);
for (int j = 0; j < columns.length; j++) {
Column c = columns[j];
int index = c.getColumnId();
try {
Value v = c.convert(r[j]);
newRow.setValue(index, v);
} catch (DbException ex) {
throw setRow(ex, count, getSQL(r));
}
}
table.validateConvertUpdateSequence(session, newRow);
boolean done = table.fireBeforeRow(session, null, newRow);
if (!done) {
table.addRow(session, newRow);
session.log(table, UndoLogRecord.INSERT, newRow);
table.fireAfterRow(session, null, newRow, false);
if (insertFromSelect) {
query.query(0, this);
} else {
ResultInterface rows = query.query(0);
while (rows.next()) {
Value[] r = rows.currentRow();
addRow(r);
}
rows.close();
}
rows.close();
}
table.fire(session, Trigger.INSERT, false);
return count;
return rowNumber;
}
public void addRow(Value[] values) {
Row newRow = table.getTemplateRow();
setCurrentRowNumber(++rowNumber);
for (int j = 0, len = columns.length; j < len; j++) {
Column c = columns[j];
int index = c.getColumnId();
try {
Value v = c.convert(values[j]);
newRow.setValue(index, v);
} catch (DbException ex) {
throw setRow(ex, rowNumber, getSQL(values));
}
}
table.validateConvertUpdateSequence(session, newRow);
boolean done = table.fireBeforeRow(session, null, newRow);
if (!done) {
table.addRow(session, newRow);
session.log(table, UndoLogRecord.INSERT, newRow);
table.fireAfterRow(session, null, newRow, false);
}
}
public String getPlanSQL() {
......@@ -204,7 +214,7 @@ public class Insert extends Prepared {
if (expr.length != columns.length) {
throw DbException.get(ErrorCode.COLUMN_COUNT_DOES_NOT_MATCH);
}
for (int i = 0; i < expr.length; i++) {
for (int i = 0, len = expr.length; i < len; i++) {
Expression e = expr[i];
if (e != null) {
e = e.optimize(session);
......@@ -240,4 +250,8 @@ public class Insert extends Prepared {
return CommandInterface.INSERT;
}
public void setInsertFromSelect(boolean value) {
this.insertFromSelect = value;
}
}
h2/src/main/org/h2/command/dml/Query.java
浏览文件 @ 8cd9dc21
......@@ -21,6 +21,7 @@ import org.h2.expression.ValueExpression;
import org.h2.message.DbException;
import org.h2.result.LocalResult;
import org.h2.result.ResultInterface;
import org.h2.result.ResultTarget;
import org.h2.result.SortOrder;
import org.h2.table.ColumnResolver;
import org.h2.table.Table;
......@@ -62,12 +63,15 @@ public abstract class Query extends Prepared {
}
/**
* Execute the query without checking the cache.
* Execute the query without checking the cache. If a target is specified,
* the results are written to it, and the method returns null. If no target
* is specified, a new LocalResult is created and returned.
*
* @param limit the limit as specified in the JDBC method call
* @param target the target to write results to
* @return the result
*/
protected abstract LocalResult queryWithoutCache(int limit);
protected abstract LocalResult queryWithoutCache(int limit, ResultTarget target);
/**
* Initialize the query.
......@@ -218,10 +222,21 @@ public abstract class Query extends Prepared {
return params;
}
public ResultInterface query(int limit) {
public ResultInterface query(int maxrows) {
return query(maxrows, null);
}
/**
* Execute the query, writing the result to the target result.
*
* @param maxrows the maximum number of rows to return
* @param target the target result (null will return the result)
* @return the result set (if the target is not set).
*/
ResultInterface query(int limit, ResultTarget target) {
fireBeforeSelectTriggers();
if (!session.getDatabase().getOptimizeReuseResults()) {
return queryWithoutCache(limit);
return queryWithoutCache(limit, target);
}
Value[] params = getParameterValues();
long now = session.getDatabase().getModificationDataId();
......@@ -238,7 +253,7 @@ public abstract class Query extends Prepared {
}
lastParameters = params;
closeLastResult();
lastResult = queryWithoutCache(limit);
lastResult = queryWithoutCache(limit, target);
this.lastEvaluated = now;
lastLimit = limit;
return lastResult;
......
h2/src/main/org/h2/command/dml/Select.java
浏览文件 @ 8cd9dc21
......@@ -29,6 +29,7 @@ import org.h2.index.IndexType;
import org.h2.message.DbException;
import org.h2.result.LocalResult;
import org.h2.result.ResultInterface;
import org.h2.result.ResultTarget;
import org.h2.result.Row;
import org.h2.result.SearchRow;
import org.h2.result.SortOrder;
......@@ -151,7 +152,7 @@ public class Select extends Query {
}
}
private void queryGroupSorted(int columnCount, LocalResult result) {
private void queryGroupSorted(int columnCount, ResultTarget result) {
int rowNumber = 0;
setCurrentRowNumber(0);
Value[] previousKeyValues = null;
......@@ -190,7 +191,7 @@ public class Select extends Query {
}
}
private void addGroupSortedRow(Value[] keyValues, int columnCount, LocalResult result) {
private void addGroupSortedRow(Value[] keyValues, int columnCount, ResultTarget result) {
Value[] row = new Value[columnCount];
for (int j = 0; groupIndex != null && j < groupIndex.length; j++) {
row[groupIndex[j]] = keyValues[j];
......@@ -443,7 +444,7 @@ public class Select extends Query {
return null;
}
private void queryDistinct(LocalResult result, long limitRows) {
private void queryDistinct(ResultTarget result, long limitRows) {
if (limitRows != 0 && offsetExpr != null) {
// limitRows must be long, otherwise we get an int overflow
// if limitRows is at or near Integer.MAX_VALUE
......@@ -469,7 +470,7 @@ public class Select extends Query {
Value[] row = { value };
result.addRow(row);
rowNumber++;
if ((sort == null || sortUsingIndex) && limitRows != 0 && result.getRowCount() >= limitRows) {
if ((sort == null || sortUsingIndex) && limitRows != 0 && rowNumber >= limitRows) {
break;
}
if (sampleSize > 0 && rowNumber >= sampleSize) {
......@@ -478,7 +479,7 @@ public class Select extends Query {
}
}
private void queryFlat(int columnCount, LocalResult result, long limitRows) {
private void queryFlat(int columnCount, ResultTarget result, long limitRows) {
if (limitRows != 0 && offsetExpr != null) {
// limitRows must be long, otherwise we get an int overflow
// if limitRows is at or near Integer.MAX_VALUE
......@@ -503,7 +504,7 @@ public class Select extends Query {
}
result.addRow(row);
rowNumber++;
if ((sort == null || sortUsingIndex) && limitRows != 0 && result.getRowCount() >= limitRows) {
if ((sort == null || sortUsingIndex) && limitRows != 0 && rowNumber >= limitRows) {
break;
}
if (sampleSize > 0 && rowNumber >= sampleSize) {
......@@ -516,7 +517,7 @@ public class Select extends Query {
}
}
private void queryQuick(int columnCount, LocalResult result) {
private void queryQuick(int columnCount, ResultTarget result) {
Value[] row = new Value[columnCount];
for (int i = 0; i < columnCount; i++) {
Expression expr = expressions.get(i);
......@@ -531,7 +532,7 @@ public class Select extends Query {
return result;
}
protected LocalResult queryWithoutCache(int maxRows) {
protected LocalResult queryWithoutCache(int maxRows, ResultTarget target) {
int limitRows = maxRows;
if (limitExpr != null) {
int l = limitExpr.getValue(session).getInt();
......@@ -542,13 +543,24 @@ public class Select extends Query {
}
}
int columnCount = expressions.size();
LocalResult result = new LocalResult(session, expressionArray, visibleColumnCount);
if (!sortUsingIndex || distinct) {
LocalResult result = null;
if (!SysProperties.optimizeInsertFromSelect || target == null) {
result = createLocalResult(result);
}
if (sort != null && (!sortUsingIndex || distinct)) {
result = createLocalResult(result);
result.setSortOrder(sort);
}
if (distinct && !isDistinctQuery) {
result = createLocalResult(result);
result.setDistinct();
}
if (isGroupQuery && !isGroupSortedQuery) {
result = createLocalResult(result);
}
if (limitRows != 0 || offsetExpr != null) {
result = createLocalResult(result);
}
topTableFilter.startQuery(session);
topTableFilter.reset();
boolean exclusive = isForUpdate && !isForUpdateMvcc;
......@@ -566,18 +578,19 @@ public class Select extends Query {
throw DbException.getUnsupportedException("FOR UPDATE && JOIN");
}
}
ResultTarget to = result != null ? result : target;
if (isQuickAggregateQuery) {
queryQuick(columnCount, result);
queryQuick(columnCount, to);
} else if (isGroupQuery) {
if (isGroupSortedQuery) {
queryGroupSorted(columnCount, result);
queryGroupSorted(columnCount, to);
} else {
queryGroup(columnCount, result);
}
} else if (isDistinctQuery) {
queryDistinct(result, limitRows);
queryDistinct(to, limitRows);
} else {
queryFlat(columnCount, result, limitRows);
queryFlat(columnCount, to, limitRows);
}
if (offsetExpr != null) {
result.setOffset(offsetExpr.getValue(session).getInt());
......@@ -585,8 +598,22 @@ public class Select extends Query {
if (limitRows != 0) {
result.setLimit(limitRows);
}
result.done();
return result;
if (result != null) {
result.done();
if (target != null) {
while (result.next()) {
target.addRow(result.currentRow());
}
result.close();
return null;
}
return result;
}
return null;
}
private LocalResult createLocalResult(LocalResult old) {
return old != null ? old : new LocalResult(session, expressionArray, visibleColumnCount);
}
private void expandColumnList() {
......
h2/src/main/org/h2/command/dml/SelectUnion.java
浏览文件 @ 8cd9dc21
......@@ -20,6 +20,7 @@ import org.h2.expression.ValueExpression;
import org.h2.message.DbException;
import org.h2.result.LocalResult;
import org.h2.result.ResultInterface;
import org.h2.result.ResultTarget;
import org.h2.result.SortOrder;
import org.h2.table.Column;
import org.h2.table.ColumnResolver;
......@@ -118,16 +119,27 @@ public class SelectUnion extends Query {
return new LocalResult(session, expressionArray, columnCount);
}
protected LocalResult queryWithoutCache(int maxrows) {
protected LocalResult queryWithoutCache(int maxrows, ResultTarget target) {
if (maxrows != 0) {
if (limitExpr != null) {
maxrows = Math.min(limitExpr.getValue(session).getInt(), maxrows);
}
limitExpr = ValueExpression.get(ValueInt.get(maxrows));
}
if (SysProperties.optimizeInsertFromSelect) {
if (unionType == UNION_ALL && target != null) {
if (sort == null && !distinct && maxrows == 0 && offsetExpr == null && limitExpr == null) {
left.query(0, target);
right.query(0, target);
return null;
}
}
}
int columnCount = left.getColumnCount();
LocalResult result = new LocalResult(session, expressionArray, columnCount);
result.setSortOrder(sort);
if (sort != null) {
result.setSortOrder(sort);
}
if (distinct) {
left.setDistinct(true);
right.setDistinct(true);
......@@ -197,6 +209,13 @@ public class SelectUnion extends Query {
result.setLimit(limitExpr.getValue(session).getInt());
}
result.done();
if (target != null) {
while (result.next()) {
target.addRow(result.currentRow());
}
result.close();
return null;
}
return result;
}
......@@ -350,9 +369,9 @@ public class SelectUnion extends Query {
return buff.toString();
}
public ResultInterface query(int limit) {
public ResultInterface query(int limit, ResultTarget target) {
// union doesn't always know the parameter list of the left and right queries
return queryWithoutCache(limit);
return queryWithoutCache(limit, target);
}
public boolean isEverything(ExpressionVisitor visitor) {
......
h2/src/main/org/h2/constant/SysProperties.java
浏览文件 @ 8cd9dc21
......@@ -480,6 +480,14 @@ public class SysProperties {
*/
public static final int OBJECT_CACHE_SIZE = MathUtils.nextPowerOf2(getIntSetting("h2.objectCacheSize", 1024));
/**
* System property <code>h2.optimizeInsertFromSelect</code>
* (default: false).<br />
* Insert into table from query directly bypassing temporary disk storage.
* This also applies to create table as select.
*/
public static boolean optimizeInsertFromSelect = getBooleanSetting("h2.optimizeInsertFromSelect", false);
/**
* System property <code>h2.optimizeDistinct</code> (default: true).<br />
* Improve the performance of simple DISTINCT queries if an index is
......
h2/src/main/org/h2/result/LocalResult.java
浏览文件 @ 8cd9dc21
......@@ -25,7 +25,7 @@ import org.h2.value.ValueArray;
* and it is also used directly by the ResultSet class in the embedded mode.
* If the result does not fit in memory, it is written to a temporary file.
*/
public class LocalResult implements ResultInterface {
public class LocalResult implements ResultInterface, ResultTarget {
private int maxMemoryRows;
private Session session;
......@@ -78,10 +78,10 @@ public class LocalResult implements ResultInterface {
* @return the local result set
*/
public static LocalResult read(Session session, ResultSet rs, int maxrows) {
Expression[] cols = Expression.getExpressionColumns(session, rs);
int columnCount = cols.length;
LocalResult result = new LocalResult(session, cols, columnCount);
try {
Expression[] cols = Expression.getExpressionColumns(session, rs);
int columnCount = cols.length;
LocalResult result = new LocalResult(session, cols, columnCount);
for (int i = 0; (maxrows == 0 || i < maxrows) && rs.next(); i++) {
Value[] list = new Value[columnCount];
for (int j = 0; j < columnCount; j++) {
......@@ -90,11 +90,11 @@ public class LocalResult implements ResultInterface {
}
result.addRow(list);
}
result.done();
return result;
} catch (SQLException e) {
throw DbException.convert(e);
}
result.done();
return result;
}
/**
......
h2/src/main/org/h2/result/ResultTarget.java 0 → 100644
浏览文件 @ 8cd9dc21
/*
* Copyright 2004-2010 H2 Group. Multiple-Licensed under the H2 License,
* Version 1.0, and under the Eclipse Public License, Version 1.0
* (http://h2database.com/html/license.html).
* Initial Developer: H2 Group
*/
package org.h2.result;
import org.h2.value.Value;
/**
* A object where rows are written to.
*/
public interface ResultTarget {
/**
* Add the row to the result set.
*
* @param values the values
*/
void addRow(Value[] values);
}
h2/src/test/org/h2/samples/DirectInsert.java 0 → 100644
浏览文件 @ 8cd9dc21
/*
* Copyright 2004-2010 H2 Group. Multiple-Licensed under the H2 License,
* Version 1.0, and under the Eclipse Public License, Version 1.0
* (http://h2database.com/html/license.html).
* Initial Developer: H2 Group
*/
package org.h2.samples;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.SQLException;
import java.sql.Statement;
import org.h2.constant.SysProperties;
import org.h2.tools.DeleteDbFiles;
/**
* Demonstrates the benefit of using the CREATE TABLE ... AS SELECT
* optimization.
*/
public class DirectInsert {
/**
* This method is called when executing this sample application from the
* command line.
*
* @param args the command line parameters
*/
public static void main(String... args) throws Exception {
Class.forName("org.h2.Driver");
DeleteDbFiles.execute("~", "test", true);
Connection conn = DriverManager.getConnection("jdbc:h2:~/test;LOG=0", "sa", "");
Statement stat = conn.createStatement();
initialInsert(conn, stat, 200000);
for (int i = 0; i < 3; i++) {
createAsSelect(stat, true);
createAsSelect(stat, false);
}
}
private static void initialInsert(Connection conn, Statement stat, int len) throws SQLException {
stat.execute("DROP TABLE IF EXISTS TEST");
stat.execute("CREATE TABLE TEST(ID INT PRIMARY KEY, NAME VARCHAR)");
PreparedStatement prep = conn.prepareStatement("INSERT INTO TEST VALUES(?, 'Test' || SPACE(100))");
long time = System.currentTimeMillis();
for (int i = 0; i < len; i++) {
long now = System.currentTimeMillis();
if (now > time + 1000) {
time = now;
System.out.println("Inserting " + (100L * i / len) + "%");
}
prep.setInt(1, i);
prep.execute();
}
conn.commit();
}
private static void createAsSelect(Statement stat, boolean optimize) throws SQLException {
SysProperties.optimizeInsertFromSelect = optimize;
stat.execute("DROP TABLE IF EXISTS TEST2");
System.out.println("CREATE TABLE ... AS SELECT " + (optimize ? "(optimized)" : ""));
long time = System.currentTimeMillis();
stat.execute("CREATE TABLE TEST2 AS SELECT * FROM TEST");
System.out.printf("%.3f sec.\n", (System.currentTimeMillis() - time) / 1000.0);
stat.execute("INSERT INTO TEST2 SELECT * FROM TEST2");
}
}
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