Page store: change page header format

h2/src/main/org/h2/index/PageBtreeLeaf.java

@@ -20,8 +20,8 @@ import org.h2.store.PageStore;
 /**
  * A b-tree leaf page that contains index data. Format:
  * <ul>
- * <li>parent page id (0 for root): int</li>
  * <li>page type: byte</li>
+ * <li>parent page id (0 for root): int</li>
  * <li>index id: varInt</li>
  * <li>entry count: short</li>
  * <li>list of offsets: short</li>
@@ -68,8 +68,8 @@ public class PageBtreeLeaf extends PageBtree {
 
     private void read() throws SQLException {
         data.reset();
-        this.parentPageId = data.readInt();
         int type = data.readByte();
+        this.parentPageId = data.readInt();
         onlyPosition = (type & Page.FLAG_LAST) == 0;
         int indexId = data.readVarInt();
         if (indexId != index.getId()) {
@@ -233,8 +233,8 @@ public class PageBtreeLeaf extends PageBtree {
     }
 
     private void writeHead() {
-        data.writeInt(parentPageId);
         data.writeByte((byte) (Page.TYPE_BTREE_LEAF | (onlyPosition ? 0 : Page.FLAG_LAST)));
+        data.writeInt(parentPageId);
         data.writeVarInt(index.getId());
         data.writeShortInt(entryCount);
     }

h2/src/main/org/h2/index/PageBtreeNode.java

@@ -21,8 +21,8 @@ import org.h2.util.MemoryUtils;
 /**
  * A b-tree node page that contains index data. Format:
  * <ul>
- * <li>parent page id (0 for root): int</li>
  * <li>page type: byte</li>
+ * <li>parent page id (0 for root): int</li>
  * <li>index id: varInt</li>
  * <li>count of all children (-1 if not known): int</li>
  * <li>entry count: short</li>
@@ -81,8 +81,8 @@ public class PageBtreeNode extends PageBtree {
 
     private void read() throws SQLException {
         data.reset();
-        this.parentPageId = data.readInt();
         int type = data.readByte();
+        this.parentPageId = data.readInt();
         onlyPosition = (type & Page.FLAG_LAST) == 0;
         int indexId = data.readVarInt();
         if (indexId != index.getId()) {
@@ -370,8 +370,8 @@ public class PageBtreeNode extends PageBtree {
     }
 
     private void writeHead() {
-        data.writeInt(parentPageId);
         data.writeByte((byte) (Page.TYPE_BTREE_NODE | (onlyPosition ? 0 : Page.FLAG_LAST)));
+        data.writeInt(parentPageId);
         data.writeVarInt(index.getId());
         data.writeInt(rowCount);
         data.writeShortInt(entryCount);

h2/src/main/org/h2/index/PageDataLeaf.java

@@ -21,8 +21,8 @@ import org.h2.store.PageStore;
 /**
  * A leaf page that contains data of one or multiple rows. Format:
  * <ul>
- * <li>parent page id (0 for root): int</li>
  * <li>page type: byte</li>
+ * <li>parent page id (0 for root): int</li>
  * <li>table id: varInt</li>
  * <li>column count: varInt</li>
  * <li>entry count: short</li>
@@ -104,8 +104,8 @@ public class PageDataLeaf extends PageData {
 
     private void read() throws SQLException {
         data.reset();
-        this.parentPageId = data.readInt();
         int type = data.readByte();
+        this.parentPageId = data.readInt();
         int tableId = data.readVarInt();
         if (tableId != index.getId()) {
             throw Message.getSQLException(ErrorCode.FILE_CORRUPTED_1,
@@ -416,7 +416,6 @@ public class PageDataLeaf extends PageData {
     }
 
     private void writeHead() {
-        data.writeInt(parentPageId);
         int type;
         if (firstOverflowPageId == 0) {
             type = Page.TYPE_DATA_LEAF | Page.FLAG_LAST;
@@ -424,6 +423,7 @@ public class PageDataLeaf extends PageData {
             type = Page.TYPE_DATA_LEAF;
         }
         data.writeByte((byte) type);
+        data.writeInt(parentPageId);
         data.writeVarInt(index.getId());
         data.writeVarInt(columnCount);
         data.writeShortInt(entryCount);

h2/src/main/org/h2/index/PageDataNode.java

@@ -21,8 +21,8 @@ import org.h2.util.MemoryUtils;
 /**
  * A leaf page that contains data of one or multiple rows. Format:
  * <ul>
- * <li>parent page id (0 for root): int</li>
  * <li>page type: byte</li>
+ * <li>parent page id (0 for root): int</li>
  * <li>table id: varInt</li>
  * <li>count of all children (-1 if not known): int</li>
  * <li>entry count: short</li>
@@ -85,8 +85,8 @@ public class PageDataNode extends PageData {
 
     private void read() throws SQLException {
         data.reset();
-        this.parentPageId = data.readInt();
         data.readByte();
+        this.parentPageId = data.readInt();
         int indexId = data.readVarInt();
         if (indexId != index.getId()) {
             throw Message.getSQLException(ErrorCode.FILE_CORRUPTED_1,
@@ -312,8 +312,8 @@ public class PageDataNode extends PageData {
     }
 
     private void writeHead() {
-        data.writeInt(parentPageId);
         data.writeByte((byte) Page.TYPE_DATA_NODE);
+        data.writeInt(parentPageId);
         data.writeVarInt(index.getId());
         data.writeInt(rowCountStored);
         data.writeShortInt(entryCount);

h2/src/main/org/h2/index/PageDataOverflow.java

@@ -18,8 +18,8 @@ import org.h2.store.PageStore;
 /**
  * Overflow data for a leaf page. Format:
  * <ul>
- * <li>parent page id (0 for root): int (0-3)</li>
- * <li>page type: byte (4)</li>
+ * <li>page type: byte (0)</li>
+ * <li>parent page id (0 for root): int (1-4)</li>
  * <li>more data: next overflow page id: int (5-8)</li>
  * <li>last remaining size: short (5-6)</li>
  * <li>data (9-/7-)</li>
@@ -108,8 +108,8 @@ public class PageDataOverflow extends Page {
     static PageDataOverflow create(PageStore store, int page, int type, int parentPageId, int next, Data all, int offset, int size) {
         Data data = store.createData();
         PageDataOverflow p = new PageDataOverflow(store, page, data);
-        data.writeInt(parentPageId);
         data.writeByte((byte) type);
+        data.writeInt(parentPageId);
         if (type == Page.TYPE_DATA_OVERFLOW) {
             data.writeInt(next);
         } else {
@@ -129,8 +129,8 @@ public class PageDataOverflow extends Page {
      */
     private void read() throws SQLException {
         data.reset();
-        parentPageId = data.readInt();
         type = data.readByte();
+        parentPageId = data.readInt();
         if (type == (Page.TYPE_DATA_OVERFLOW | Page.FLAG_LAST)) {
             size = data.readShortInt();
             nextPage = 0;
@@ -168,8 +168,8 @@ public class PageDataOverflow extends Page {
     }
 
     private void writeHead() {
-        data.writeInt(parentPageId);
         data.writeByte((byte) type);
+        data.writeInt(parentPageId);
     }
 
     public void write(DataPage buff) throws SQLException {

h2/src/main/org/h2/store/PageFreeList.java

@@ -6,23 +6,20 @@
 package org.h2.store;
 
 import java.sql.SQLException;
-import org.h2.constant.ErrorCode;
 import org.h2.engine.Session;
-import org.h2.message.Message;
 import org.h2.util.BitField;
 
 /**
  * The list of free pages of a page store. The format of a free list trunk page
  * is:
  * <ul>
- * <li>parent page id (always 0): int</li>
  * <li>page type: byte</li>
- * <li>data (5-)</li>
+ * <li>data (1-)</li>
  * </ul>
  */
 public class PageFreeList extends Page {
 
-    private static final int DATA_START = 5;
+    private static final int DATA_START = 1;
 
     private final PageStore store;
     private final BitField used = new BitField();
@@ -45,7 +42,7 @@ public class PageFreeList extends Page {
      * @param pageId the page id
      * @return the page
      */
-    static PageFreeList read(PageStore store, Data data, int pageId) throws SQLException {
+    static PageFreeList read(PageStore store, Data data, int pageId) {
         PageFreeList p = new PageFreeList(store, pageId);
         p.data = data;
         p.read();
@@ -140,14 +137,9 @@ public class PageFreeList extends Page {
     /**
      * Read the page from the disk.
      */
-    private void read() throws SQLException {
+    private void read() {
         data.reset();
-        int p = data.readInt();
-        int t = data.readByte();
-        if (p != 0) {
-            throw Message.getSQLException(ErrorCode.FILE_CORRUPTED_1, "pos:" + getPos() + " type:" + t + " parent:" + p
-                    + " expected type:" + Page.TYPE_FREE_LIST);
-        }
+        data.readByte();
         for (int i = 0; i < pageCount; i += 8) {
             used.setByte(i, data.readByte() & 255);
         }
@@ -160,9 +152,7 @@ public class PageFreeList extends Page {
 
     public void write(DataPage buff) throws SQLException {
         data = store.createData();
-        data.writeInt(0);
-        int type = Page.TYPE_FREE_LIST;
-        data.writeByte((byte) type);
+        data.writeByte((byte) Page.TYPE_FREE_LIST);
         for (int i = 0; i < pageCount; i += 8) {
             data.writeByte((byte) used.getByte(i));
         }

h2/src/main/org/h2/store/PageStore.java

@@ -454,8 +454,8 @@ public class PageStore implements CacheWriter {
         }
         Data data = createData();
         readPage(pageId, data);
-        data.readInt();
         int type = data.readByte();
+        data.readInt();
         Page p;
         switch (type & ~Page.FLAG_LAST) {
         case Page.TYPE_EMPTY:

h2/src/main/org/h2/store/PageStreamData.java

@@ -12,8 +12,8 @@ import org.h2.engine.Session;
 /**
  * A data page of a stream. The format is:
  * <ul>
- * <li>the trunk page id: int (0-3)</li>
- * <li>page type: byte (4)</li>
+ * <li>page type: byte (0)</li>
+ * <li>the trunk page id: int (1-4)</li>
  * <li>log key: int (5-8)</li>
  * <li>data (9-)</li>
  * </ul>
@@ -68,8 +68,8 @@ public class PageStreamData extends Page {
      */
     private void read() {
         data.reset();
-        trunk = data.readInt();
         data.readByte();
+        trunk = data.readInt();
         logKey = data.readInt();
     }
 
@@ -82,8 +82,8 @@ public class PageStreamData extends Page {
      */
     void initWrite() {
         data = store.createData();
-        data.writeInt(trunk);
         data.writeByte((byte) Page.TYPE_STREAM_DATA);
+        data.writeInt(trunk);
         data.writeInt(logKey);
         remaining = store.getPageSize() - data.length();
     }

h2/src/main/org/h2/store/PageStreamTrunk.java

@@ -13,8 +13,8 @@ import org.h2.engine.Session;
  * A trunk page of a stream. It contains the page numbers of the stream, and the
  * page number of the next trunk. The format is:
  * <ul>
- * <li>previous trunk page, or 0 if none: int (0-3)</li>
- * <li>page type: byte (4)</li>
+ * <li>page type: byte (0)</li>
+ * <li>previous trunk page, or 0 if none: int (1-4)</li>
  * <li>log key: int (5-8)</li>
  * <li>next trunk page: int (9-12)</li>
  * <li>number of pages: short (13-14)</li>
@@ -84,8 +84,8 @@ public class PageStreamTrunk extends Page {
      */
     private void read() {
         data.reset();
-        parent = data.readInt();
         data.readByte();
+        parent = data.readInt();
         logKey = data.readInt();
         nextTrunk = data.readInt();
         pageCount = data.readShortInt();
@@ -123,8 +123,8 @@ public class PageStreamTrunk extends Page {
 
     public void write(DataPage buff) throws SQLException {
         data = store.createData();
-        data.writeInt(parent);
         data.writeByte((byte) Page.TYPE_STREAM_TRUNK);
+        data.writeInt(parent);
         data.writeInt(logKey);
         data.writeInt(nextTrunk);
         data.writeShortInt(pageCount);

h2/src/main/org/h2/tools/Recover.java

@@ -859,14 +859,10 @@ public class Recover extends Tool implements DataHandler {
                 s = Data.create(this, pageSize);
                 store.seek(page * pageSize);
                 store.readFully(s.getBytes(), 0, pageSize);
-                int parentPageId = s.readInt();
                 int type = s.readByte();
                 switch (type) {
                 case Page.TYPE_EMPTY:
                     pageTypeCount[type]++;
-                    if (parentPageId != 0) {
-                        writer.println("-- ERROR empty page with parent: " + parentPageId);
-                    }
                     emptyPages++;
                     continue;
                 }
@@ -876,20 +872,24 @@ public class Recover extends Tool implements DataHandler {
                 // type 1
                 case Page.TYPE_DATA_LEAF: {
                     pageTypeCount[type]++;
+                    int parentPageId = s.readInt();
                     setStorage(s.readVarInt());
                     int columnCount = s.readVarInt();
                     int entries = s.readShortInt();
-                    writer.println("-- page " + page + ": data leaf " + (last ? "(last)" : "") + " table: " + storageId + " entries: " + entries + " columns: " + columnCount);
+                    writer.println("-- page " + page + ": data leaf " + (last ? "(last)" : "") + " parent: " + parentPageId +
+                            " table: " + storageId + " entries: " + entries + " columns: " + columnCount);
                     dumpPageDataLeaf(writer, s, last, page, columnCount, entries);
                     break;
                 }
                 // type 2
                 case Page.TYPE_DATA_NODE: {
                     pageTypeCount[type]++;
+                    int parentPageId = s.readInt();
                     setStorage(s.readVarInt());
                     int rowCount = s.readInt();
                     int entries = s.readShortInt();
-                    writer.println("-- page " + page + ": data node " + (last ? "(last)" : "") + " entries: " + entries + " rowCount: " + rowCount);
+                    writer.println("-- page " + page + ": data node " + (last ? "(last)" : "") + " parent: " + parentPageId +
+                            " entries: " + entries + " rowCount: " + rowCount);
                     break;
                 }
                 // type 3
@@ -900,9 +900,11 @@ public class Recover extends Tool implements DataHandler {
                 // type 4
                 case Page.TYPE_BTREE_LEAF: {
                     pageTypeCount[type]++;
+                    int parentPageId = s.readInt();
                     setStorage(s.readVarInt());
                     int entries = s.readShortInt();
-                    writer.println("-- page " + page + ": b-tree leaf " + (last ? "(last)" : "") + " index: " + storageId + " entries: " + entries);
+                    writer.println("-- page " + page + ": b-tree leaf " + (last ? "(last)" : "") + " parent: " + parentPageId +
+                            " index: " + storageId + " entries: " + entries);
                     if (trace) {
                         dumpPageBtreeLeaf(writer, s, entries, !last);
                     }
@@ -911,8 +913,10 @@ public class Recover extends Tool implements DataHandler {
                 // type 5
                 case Page.TYPE_BTREE_NODE:
                     pageTypeCount[type]++;
+                    int parentPageId = s.readInt();
                     setStorage(s.readVarInt());
-                    writer.println("-- page " + page + ": b-tree node" + (last ? "(last)" : "") +  " index: " + storageId);
+                    writer.println("-- page " + page + ": b-tree node" + (last ? "(last)" : "") +  " parent: " + parentPageId +
+                            "index: " + storageId);
                     if (trace) {
                         dumpPageBtreeNode(writer, s, !last);
                     }
@@ -1107,8 +1111,8 @@ public class Recover extends Tool implements DataHandler {
                     store.seek((long) trunkPage * pageSize);
                     store.readFully(page.getBytes(), 0, pageSize);
                     page.reset();
-                    page.readInt();
                     int t = page.readByte();
+                    page.readInt();
                     if (t != Page.TYPE_STREAM_TRUNK) {
                         writer.println("-- eof  page: " +trunkPage + " type: " + t + " expected type: " + Page.TYPE_STREAM_TRUNK);
                         endOfFile = true;
@@ -1140,8 +1144,8 @@ public class Recover extends Tool implements DataHandler {
                 store.seek((long) nextPage * pageSize);
                 store.readFully(page.getBytes(), 0, pageSize);
                 page.reset();
-                int p = page.readInt();
                 int t = page.readByte();
+                int p = page.readInt();
                 int k = page.readInt();
                 if (t != Page.TYPE_STREAM_DATA) {
                     writer.println("-- eof  page: " +nextPage+ " type: " + t + " parent: " + p +