MVStore: compacting a store with an R-tree did not always work.

h2/src/main/org/h2/mvstore/MVMap.java

@@ -249,7 +249,7 @@ public class MVMap<K, V> extends AbstractMap<K, V>
                 }
                 return (K) p.getKey((int) (index - offset));
             }
-            int i = 0, size = p.getChildPageCount();
+            int i = 0, size = getChildPageCount(p);
             for (; i < size; i++) {
                 long c = p.getCounts(i);
                 if (index < c + offset) {
@@ -348,7 +348,7 @@ public class MVMap<K, V> extends AbstractMap<K, V>
             if (p.isLeaf()) {
                 return (K) p.getKey(first ? 0 : p.getKeyCount() - 1);
             }
-            p = p.getChildPage(first ? 0 : p.getChildPageCount() - 1);
+            p = p.getChildPage(first ? 0 : getChildPageCount(p) - 1);
         }
     }
 
@@ -427,7 +427,7 @@ public class MVMap<K, V> extends AbstractMap<K, V>
             x++;
         }
         while (true) {
-            if (x < 0 || x >= p.getChildPageCount()) {
+            if (x < 0 || x >= getChildPageCount(p)) {
                 return null;
             }
             K k = getMinMax(p.getChildPage(x), key, min, excluding);
@@ -480,34 +480,6 @@ public class MVMap<K, V> extends AbstractMap<K, V>
         return get(key) != null;
     }
 
-    /**
-     * Get a key that is referenced in the given page or a child page.
-     *
-     * @param p the page
-     * @return the key, or null if not found
-     */
-    protected K getLiveKey(Page p) {
-        while (!p.isLeaf()) {
-            p = p.getLiveChildPage(0);
-            if (p == null) {
-                return null;
-            }
-        }
-        @SuppressWarnings("unchecked")
-        K key = (K) p.getKey(0);
-        Page p2 = binarySearchPage(root, key);
-        if (p2 == null) {
-            return null;
-        }
-        if (p2.getPos() == 0) {
-            return p2 == p ? key : null;
-        }
-        if (p2.getPos() == p.getPos()) {
-            return key;
-        }
-        return null;
-    }
-
     /**
      * Get the value for the given key, or null if not found.
      *
@@ -846,7 +818,7 @@ public class MVMap<K, V> extends AbstractMap<K, V>
             return 1;
         }
         int writtenPageCount = 0;
-        for (int i = 0; i < p.getChildPageCount(); i++) {
+        for (int i = 0; i < getChildPageCount(p); i++) {
             long childPos = p.getChildPagePos(i);
             if (childPos != 0 && DataUtils.getPageType(childPos) == DataUtils.PAGE_TYPE_LEAF) {
                 // we would need to load the page, and it's a leaf:
@@ -1250,7 +1222,7 @@ public class MVMap<K, V> extends AbstractMap<K, V>
      * @return the number of direct children
      */
     protected int getChildPageCount(Page p) {
-        return p.getChildPageCount();
+        return p.getRawChildPageCount();
     }
 
     /**
@@ -1314,12 +1286,13 @@ public class MVMap<K, V> extends AbstractMap<K, V>
             }
         } else {
             CursorPos pos = new CursorPos(target, 0, parent);
-            for (int i = 0; i < target.getChildPageCount(); i++) {
+            for (int i = 0; i < getChildPageCount(target); i++) {
                 pos.index = i;
                 long p = source.getChildPagePos(i);
                 if (p != 0) {
                     // p == 0 means no child
                     // (for example the last entry of an r-tree node)
+                    // (the MVMap is also used for r-trees for compacting)
                     copy(source.getChildPage(i), pos);
                 }
             }

h2/src/main/org/h2/mvstore/Page.java

@@ -617,7 +617,7 @@ public class Page {
      */
     void removeAllRecursive() {
         if (children != null) {
-            for (int i = 0, size = childCount; i < size; i++) {
+            for (int i = 0, size = map.getChildPageCount(this); i < size; i++) {
                 PageReference ref = children[i];
                 if (ref.page != null) {
                     ref.page.removeAllRecursive();
@@ -990,7 +990,7 @@ public class Page {
         return version;
     }
 
-    public int getChildPageCount() {
+    public int getRawChildPageCount() {
         return childCount;
     }
 
@@ -1041,7 +1041,7 @@ public class Page {
                 mem += valueType.getMemory(values[i]);
             }
         } else {
-            mem += this.getChildPageCount() * DataUtils.PAGE_MEMORY_CHILD;
+            mem += this.getRawChildPageCount() * DataUtils.PAGE_MEMORY_CHILD;
         }
         addMemory(mem - memory);
     }

h2/src/main/org/h2/mvstore/rtree/MVRTreeMap.java

@@ -120,48 +120,6 @@ public class MVRTreeMap<V> extends MVMap<SpatialKey, V> {
         return null;
     }
 
-    @Override
-    protected SpatialKey getLiveKey(Page p) {
-        while (!p.isLeaf()) {
-            p = p.getLiveChildPage(0);
-            if (p == null) {
-                return null;
-            }
-        }
-        SpatialKey key = (SpatialKey) p.getKey(0);
-        Page p2 = getPage(root, key);
-        if (p2 == null) {
-            return null;
-        }
-        if (p2.getPos() == 0) {
-            return p2 == p ? key : null;
-        }
-        if (p2.getPos() == p.getPos()) {
-            return key;
-        }
-        return null;
-    }
-
-    private Page getPage(Page p, Object key) {
-        if (!p.isLeaf()) {
-            for (int i = 0; i < p.getKeyCount(); i++) {
-                if (contains(p, i, key)) {
-                    Page x = getPage(p.getChildPage(i), key);
-                    if (x != null) {
-                        return x;
-                    }
-                }
-            }
-        } else {
-            for (int i = 0; i < p.getKeyCount(); i++) {
-                if (keyType.equals(p.getKey(i), key)) {
-                    return p;
-                }
-            }
-        }
-        return null;
-    }
-
     @Override
     protected Object remove(Page p, long writeVersion, Object key) {
         Object result = null;
@@ -508,7 +466,7 @@ public class MVRTreeMap<V> extends MVMap<SpatialKey, V> {
 
     @Override
     protected int getChildPageCount(Page p) {
-        return p.getChildPageCount() - 1;
+        return p.getRawChildPageCount() - 1;
     }
 
     /**

h2/src/test/org/h2/test/db/TestSpatial.java

@@ -87,6 +87,7 @@ public class TestSpatial extends TestBase {
         testValueGeometryScript();
         testInPlaceUpdate();
         testScanIndexOnNonSpatialQuery();
+        testStoreCorruption();
     }
 
     private void testHashCode() {
@@ -851,4 +852,31 @@ public class TestSpatial extends TestBase {
         }
         deleteDb("spatial");
     }
+
+    private void testStoreCorruption() throws SQLException {
+        deleteDb("spatial");
+        Connection conn = getConnection(url);
+        try {
+            Statement stat = conn.createStatement();
+            stat.execute("drop table if exists pt_cloud;\n" +
+                    "CREATE TABLE PT_CLOUD AS SELECT CONCAT('POINT(',A.X,' ',B.X,')')::geometry the_geom from" +
+                    " system_range(1e6,1e6+10) A,system_range(6e6,6e6+10) B;\n" +
+                    "create spatial index ptindex on pt_cloud(the_geom);");
+            // Wait some time
+            try {
+                Thread.sleep(1000);
+            } catch (InterruptedException ex) {
+                throw new SQLException(ex);
+            }
+            stat.execute("drop table if exists pt_cloud;\n" +
+                    "CREATE TABLE PT_CLOUD AS SELECT CONCAT('POINT(',A.X,' ',B.X,')')::geometry the_geom from" +
+                    " system_range(1e6,1e6+50) A,system_range(6e6,6e6+50) B;\n" +
+                    "create spatial index ptindex on pt_cloud(the_geom);\n" +
+                    "shutdown compact;");
+        } finally {
+            // Close the database
+            conn.close();
+        }
+        deleteDb("spatial");
+    }
 }