New experimental page store.

h2/src/main/org/h2/engine/Database.java

@@ -572,17 +572,17 @@ public class Database implements DataHandler {
             while (!beforeWriting()) {
                 // until we can write (file are not open - no need to re-connect)
             }
-            if (SysProperties.PAGE_STORE) {
-                starting = true;
-                getPageStore();
-                starting = false;
-            }
             if (exists) {
                 lobFilesInDirectories &= !ValueLob.existsLobFile(getDatabasePath());
                 lobFilesInDirectories |= FileUtils.exists(databaseName + Constants.SUFFIX_LOBS_DIRECTORY);
             }
             dummy = DataPage.create(this, 0);
             deleteOldTempFiles();
+            if (SysProperties.PAGE_STORE) {
+                starting = true;
+                getPageStore();
+                starting = false;
+            }
             log = new LogSystem(this, databaseName, readOnly, accessModeLog, pageStore);
             if (pageStore == null) {
                 openFileData();

h2/src/main/org/h2/engine/Session.java

@@ -101,7 +101,7 @@ public class Session extends SessionWithState {
     private int modificationIdState;
     private int objectId;
 
-    Session(Database database, User user, int id) {
+    public Session(Database database, User user, int id) {
         this.database = database;
         this.undoLog = new UndoLog(this);
         this.user = user;

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

@@ -62,7 +62,7 @@ abstract class PageBtree extends Record {
     protected boolean onlyPosition;
 
     /**
-     * If the page was already written to the buffer.
+     * Whether the data page is up-to-date.
      */
     protected boolean written;
 
@@ -181,6 +181,7 @@ abstract class PageBtree extends Record {
      * @param id the new page id
      */
     void setPageId(int id) throws SQLException {
+        written = false;
         index.getPageStore().removeRecord(getPos());
         setPos(id);
         remapChildren();
@@ -210,7 +211,8 @@ abstract class PageBtree extends Record {
      * @param id the new parent page id
      */
     void setParentPageId(int id) {
-        this.parentPageId = id;
+        written = false;
+        parentPageId = id;
     }
 
     /**

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

@@ -80,7 +80,7 @@ public class PageBtreeCursor implements Cursor {
         if (current == null) {
             return false;
         }
-        if (i <= 0) {
+        if (i < 0) {
             current.previousPage(this);
             if (current == null) {
                 return false;

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

@@ -31,7 +31,7 @@ public class PageBtreeIndex extends BaseIndex {
 
     private PageStore store;
     private TableData tableData;
-    private int headPos;
+    private final int headPos;
     private long rowCount;
     private boolean needRebuild;
 
@@ -46,6 +46,7 @@ public class PageBtreeIndex extends BaseIndex {
         tableData = table;
         if (!database.isPersistent() || id < 0) {
             int todo;
+            this.headPos = 0;
             return;
         }
         this.store = database.getPageStore();
@@ -53,13 +54,19 @@ public class PageBtreeIndex extends BaseIndex {
             // new index
             needRebuild = true;
             this.headPos = headPos = store.allocatePage();
+            // TODO currently the head position is stored in the log
+            // it should not for new tables, otherwise redo of other operations
+            // must ensure this page is not used for other things
+            store.addMeta(this, session, headPos);
             PageBtreeLeaf root = new PageBtreeLeaf(this, headPos, Page.ROOT, store.createDataPage());
             store.updateRecord(root, true, root.data);
-            store.addMeta(this, session);
         } else {
             this.headPos = headPos;
             PageBtree root = getPage(headPos);
             rowCount = root.getRowCount();
+            if (rowCount == 0 && store.isRecoveryRunning()) {
+                needRebuild = true;
+            }
             if (!database.isReadOnly()) {
                 // could have been created before, but never committed
                 // TODO test if really required

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

@@ -48,6 +48,11 @@ abstract class PageData extends Record {
      */
     protected int[] keys;
 
+    /**
+     * Whether the data page is up-to-date.
+     */
+    protected boolean written;
+
     PageData(PageScanIndex index, int pageId, int parentPageId, DataPage data) {
         this.index = index;
         this.parentPageId = parentPageId;
@@ -137,6 +142,7 @@ abstract class PageData extends Record {
      * @param id the new page id
      */
     void setPageId(int id) throws SQLException {
+        written = false;
         index.getPageStore().removeRecord(getPos());
         setPos(id);
         remapChildren();
@@ -166,7 +172,8 @@ abstract class PageData extends Record {
      * @param id the new parent page id
      */
     void setParentPageId(int id) {
-        this.parentPageId = id;
+        written = false;
+        parentPageId = id;
     }
 
     /**
@@ -204,4 +211,8 @@ abstract class PageData extends Record {
         return index.getPageStore().getPageSize() >> 2;
     }
 
+    int getParentPageId() {
+        return parentPageId;
+    }
+
 }

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

@@ -52,8 +52,6 @@ class PageDataLeaf extends PageData {
      */
     int start;
 
-    private boolean written;
-
     PageDataLeaf(PageScanIndex index, int pageId, int parentPageId, DataPage data) {
         super(index, pageId, parentPageId, data);
         start = KEY_OFFSET_PAIR_START;
@@ -263,7 +261,7 @@ class PageDataLeaf extends PageData {
         if (parentPageId == Page.ROOT) {
             return null;
         }
-        PageDataNode next = (PageDataNode) index.getPage(parentPageId);
+        PageDataNode next = (PageDataNode) index.getPage(parentPageId, -1);
         return next.getNextPage(keys[entryCount - 1]);
     }
 

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

@@ -80,7 +80,7 @@ class PageDataNode extends PageData {
     int addRowTry(Row row) throws SQLException {
         while (true) {
             int x = find(row.getPos());
-            PageData page = index.getPage(childPageIds[x]);
+            PageData page = index.getPage(childPageIds[x], getPos());
             int splitPoint = page.addRowTry(row);
             if (splitPoint == 0) {
                 break;
@@ -113,7 +113,7 @@ class PageDataNode extends PageData {
 
     Cursor find(Session session) throws SQLException {
         int child = childPageIds[0];
-        return index.getPage(child).find(session);
+        return index.getPage(child, getPos()).find(session);
     }
 
     PageData split(int splitPoint) throws SQLException {
@@ -134,7 +134,7 @@ class PageDataNode extends PageData {
 
     protected void remapChildren() throws SQLException {
         for (int child : childPageIds) {
-            PageData p = index.getPage(child);
+            PageData p = index.getPage(child, -1);
             p.setParentPageId(getPos());
             index.getPageStore().updateRecord(p, true, p.data);
         }
@@ -156,7 +156,7 @@ class PageDataNode extends PageData {
 
     int getLastKey() throws SQLException {
         int todoRemove;
-        return index.getPage(childPageIds[entryCount]).getLastKey();
+        return index.getPage(childPageIds[entryCount], getPos()).getLastKey();
     }
 
     /**
@@ -171,23 +171,23 @@ class PageDataNode extends PageData {
             if (parentPageId == Page.ROOT) {
                 return null;
             }
-            PageDataNode next = (PageDataNode) index.getPage(parentPageId);
+            PageDataNode next = (PageDataNode) index.getPage(parentPageId, -1);
             return next.getNextPage(key);
         }
-        PageData page = index.getPage(childPageIds[i]);
+        PageData page = index.getPage(childPageIds[i], getPos());
         return page.getFirstLeaf();
     }
 
     PageDataLeaf getFirstLeaf() throws SQLException {
         int child = childPageIds[0];
-        return index.getPage(child).getFirstLeaf();
+        return index.getPage(child, getPos()).getFirstLeaf();
     }
 
     boolean remove(int key) throws SQLException {
         int at = find(key);
         // merge is not implemented to allow concurrent usage of btrees
         // TODO maybe implement merge
-        PageData page = index.getPage(childPageIds[at]);
+        PageData page = index.getPage(childPageIds[at], getPos());
         boolean empty = page.remove(key);
         updateRowCount(-1);
         if (!empty) {
@@ -208,7 +208,7 @@ class PageDataNode extends PageData {
     void freeChildren() throws SQLException {
         for (int i = 0; i <= entryCount; i++) {
             int childPageId = childPageIds[i];
-            PageData child = index.getPage(childPageId);
+            PageData child = index.getPage(childPageId, getPos());
             index.getPageStore().freePage(childPageId, false, null);
             child.freeChildren();
         }
@@ -216,7 +216,7 @@ class PageDataNode extends PageData {
 
     Row getRow(int key) throws SQLException {
         int at = find(key);
-        PageData page = index.getPage(childPageIds[at]);
+        PageData page = index.getPage(childPageIds[at], getPos());
         return page.getRow(key);
     }
 
@@ -224,7 +224,7 @@ class PageDataNode extends PageData {
         if (rowCount == UNKNOWN_ROWCOUNT) {
             int count = 0;
             for (int child : childPageIds) {
-                PageData page = index.getPage(child);
+                PageData page = index.getPage(child, getPos());
                 if (getPos() == page.getPos()) {
                     throw Message.throwInternalError("Page it its own child: " + getPageId());
                 }

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

@@ -65,7 +65,10 @@ public class PageScanIndex extends BaseIndex implements RowIndex {
         if (headPos == Index.EMPTY_HEAD) {
             // new table
             this.headPos = headPos = store.allocatePage();
-            store.addMeta(this, session);
+            // TODO currently the head position is stored in the log
+            // it should not for new tables, otherwise redo of other operations
+            // must ensure this page is not used for other things
+            store.addMeta(this, session, headPos);
             PageDataLeaf root = new PageDataLeaf(this, headPos, Page.ROOT, store.createDataPage());
             store.updateRecord(root, true, root.data);
 
@@ -76,7 +79,7 @@ public class PageScanIndex extends BaseIndex implements RowIndex {
 //            store.updateRecord(root, true, root.data);
         } else {
             this.headPos = headPos;
-            PageData root = getPage(headPos);
+            PageData root = getPage(headPos, 0);
             lastKey = root.getLastKey();
             rowCount = root.getRowCount();
             // could have been created before, but never committed
@@ -118,7 +121,7 @@ public class PageScanIndex extends BaseIndex implements RowIndex {
             }
         }
         while (true) {
-            PageData root = getPage(headPos);
+            PageData root = getPage(headPos, 0);
             int splitPoint = root.addRowTry(row);
             if (splitPoint == 0) {
                 break;
@@ -159,9 +162,10 @@ public class PageScanIndex extends BaseIndex implements RowIndex {
      * Read the given page.
      *
      * @param id the page id
+     * @param parent the parent, or -1 if unknown
      * @return the page
      */
-    PageData getPage(int id) throws SQLException {
+    PageData getPage(int id, int parent) throws SQLException {
         Record rec = store.getRecord(id);
         if (rec != null) {
             return (PageData) rec;
@@ -185,6 +189,11 @@ public class PageScanIndex extends BaseIndex implements RowIndex {
             throw Message.getSQLException(ErrorCode.FILE_CORRUPTED_1, "page=" + id + " type=" + type);
         }
         result.read();
+        if (parent != -1) {
+            if (result.getParentPageId() != parent) {
+                throw Message.throwInternalError(result.getParentPageId() + " " + parent + " " + result);
+            }
+        }
         return result;
     }
 
@@ -193,7 +202,7 @@ public class PageScanIndex extends BaseIndex implements RowIndex {
     }
 
     public Cursor find(Session session, SearchRow first, SearchRow last) throws SQLException {
-        PageData root = getPage(headPos);
+        PageData root = getPage(headPos, 0);
         return root.find(session);
     }
 
@@ -229,7 +238,7 @@ public class PageScanIndex extends BaseIndex implements RowIndex {
             removeAllRows();
         } else {
             int key = row.getPos();
-            PageData root = getPage(headPos);
+            PageData root = getPage(headPos, 0);
             root.remove(key);
             rowCount--;
             int todoReuseKeys;
@@ -276,7 +285,7 @@ public class PageScanIndex extends BaseIndex implements RowIndex {
     }
 
     private void removeAllRows() throws SQLException {
-        PageData root = getPage(headPos);
+        PageData root = getPage(headPos, 0);
         root.freeChildren();
         root = new PageDataLeaf(this, headPos, Page.ROOT, store.createDataPage());
         store.removeRecord(headPos);
@@ -290,7 +299,7 @@ public class PageScanIndex extends BaseIndex implements RowIndex {
     }
 
     public Row getRow(Session session, int key) throws SQLException {
-        PageData root = getPage(headPos);
+        PageData root = getPage(headPos, 0);
         return root.getRow(key);
     }