wip

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

@@ -6,8 +6,6 @@
 package org.h2.index;
 
 import java.util.ArrayList;
-import java.util.List;
-import java.util.concurrent.Future;
 import org.h2.api.ErrorCode;
 import org.h2.command.Prepared;
 import org.h2.command.dml.Query;
@@ -103,12 +101,8 @@ public class ViewIndex extends BaseIndex implements SpatialIndex {
             // we do not support batching for recursive queries
             return null;
         }
-        IndexLookupBatch lookupBatch = query.isUnion() ?
-                createLookupBatchUnion((SelectUnion) query) :
-                createLookupBatchSimple((Select) query);
-        // TODO not initialize index cursor on the top table filter but work as usual batching
-        // TODO return wrapper which goes through all the joins an collects all the rows
-        return null;
+        // currently do not support unions
+        return query.isUnion() ? null : createLookupBatchSimple((Select) query);
     }
 
     private IndexLookupBatch createLookupBatchSimple(Select select) {
@@ -119,30 +113,7 @@ public class ViewIndex extends BaseIndex implements SpatialIndex {
             // our sub-query itself is not batched, will run usual way
             return null;
         }
-        // TODO wrap the join batch into lookup batch
-        return null;
-    }
-
-    private IndexLookupBatch createLookupBatchUnion(SelectUnion union) {
-        Query left = union.getLeft();
-        IndexLookupBatch leftLookupBatch = left.isUnion() ?
-                createLookupBatchUnion((SelectUnion) left):
-                createLookupBatchSimple((Select) left);
-
-        Query right = union.getRight();
-        IndexLookupBatch rightLookupBatch = right.isUnion() ?
-                createLookupBatchUnion((SelectUnion) right) :
-                createLookupBatchSimple((Select) right);
-
-        if (leftLookupBatch == null) {
-            if (rightLookupBatch == null) {
-                return null;
-            }
-            leftLookupBatch = null; // TODO
-        } else if (rightLookupBatch == null) {
-            rightLookupBatch = null; // TODO
-        }
-        return new UnionLookupBatch(leftLookupBatch, rightLookupBatch);
+        return joinBatch.asViewIndexLookupBatch(this);
     }
 
     public Session getSession() {
@@ -263,57 +234,60 @@ public class ViewIndex extends BaseIndex implements SpatialIndex {
         return (Query) p;
     }
 
-    private Cursor find(Session session, SearchRow first, SearchRow last,
+    private Cursor findRecursive(Session session, SearchRow first, SearchRow last,
             SearchRow intersection) {
-        if (recursive) {
-            LocalResult recResult = view.getRecursiveResult();
-            if (recResult != null) {
-                recResult.reset();
-                return new ViewCursor(this, recResult, first, last);
-            }
-            if (query == null) {
-                query = (Query) createSession.prepare(querySQL, true);
-            }
-            if (!query.isUnion()) {
-                throw DbException.get(ErrorCode.SYNTAX_ERROR_2,
-                        "recursive queries without UNION ALL");
-            }
-            SelectUnion union = (SelectUnion) query;
-            if (union.getUnionType() != SelectUnion.UNION_ALL) {
-                throw DbException.get(ErrorCode.SYNTAX_ERROR_2,
-                        "recursive queries without UNION ALL");
+        assert recursive;
+        LocalResult recResult = view.getRecursiveResult();
+        if (recResult != null) {
+            recResult.reset();
+            return new ViewCursor(this, recResult, first, last);
+        }
+        if (query == null) {
+            query = (Query) createSession.prepare(querySQL, true);
+        }
+        if (!query.isUnion()) {
+            throw DbException.get(ErrorCode.SYNTAX_ERROR_2,
+                    "recursive queries without UNION ALL");
+        }
+        SelectUnion union = (SelectUnion) query;
+        if (union.getUnionType() != SelectUnion.UNION_ALL) {
+            throw DbException.get(ErrorCode.SYNTAX_ERROR_2,
+                    "recursive queries without UNION ALL");
+        }
+        Query left = union.getLeft();
+        // to ensure the last result is not closed
+        left.disableCache();
+        LocalResult r = left.query(0);
+        LocalResult result = union.getEmptyResult();
+        // ensure it is not written to disk,
+        // because it is not closed normally
+        result.setMaxMemoryRows(Integer.MAX_VALUE);
+        while (r.next()) {
+            result.addRow(r.currentRow());
+        }
+        Query right = union.getRight();
+        r.reset();
+        view.setRecursiveResult(r);
+        // to ensure the last result is not closed
+        right.disableCache();
+        while (true) {
+            r = right.query(0);
+            if (r.getRowCount() == 0) {
+                break;
             }
-            Query left = union.getLeft();
-            // to ensure the last result is not closed
-            left.disableCache();
-            LocalResult r = left.query(0);
-            LocalResult result = union.getEmptyResult();
-            // ensure it is not written to disk,
-            // because it is not closed normally
-            result.setMaxMemoryRows(Integer.MAX_VALUE);
             while (r.next()) {
                 result.addRow(r.currentRow());
             }
-            Query right = union.getRight();
             r.reset();
             view.setRecursiveResult(r);
-            // to ensure the last result is not closed
-            right.disableCache();
-            while (true) {
-                r = right.query(0);
-                if (r.getRowCount() == 0) {
-                    break;
-                }
-                while (r.next()) {
-                    result.addRow(r.currentRow());
-                }
-                r.reset();
-                view.setRecursiveResult(r);
-            }
-            view.setRecursiveResult(null);
-            result.done();
-            return new ViewCursor(this, result, first, last);
         }
+        view.setRecursiveResult(null);
+        result.done();
+        return new ViewCursor(this, result, first, last);
+    }
+
+    public void setupQueryParameters(Session session, SearchRow first, SearchRow last,
+            SearchRow intersection) {
         ArrayList<Parameter> paramList = query.getParameters();
         if (originalParameters != null) {
             for (int i = 0, size = originalParameters.size(); i < size; i++) {
@@ -350,6 +324,14 @@ public class ViewIndex extends BaseIndex implements SpatialIndex {
                 setParameter(paramList, idx++, intersection.getValue(i));
             }
         }
+    }
+
+    private Cursor find(Session session, SearchRow first, SearchRow last,
+            SearchRow intersection) {
+        if (recursive) {
+            return findRecursive(session, first, last, intersection);
+        }
+        setupQueryParameters(session, first, last, intersection);
         LocalResult result = query.query(0);
         return new ViewCursor(this, result, first, last);
     }
@@ -506,42 +488,4 @@ public class ViewIndex extends BaseIndex implements SpatialIndex {
     public boolean isRecursive() {
         return recursive;
     }
-
-    /**
-     * Lookup batch for unions.
-     */
-    private static final class UnionLookupBatch implements IndexLookupBatch {
-        private final IndexLookupBatch left;
-        private final IndexLookupBatch right;
-
-        private UnionLookupBatch(IndexLookupBatch left, IndexLookupBatch right) {
-            this.left = left;
-            this.right = right;
-        }
-
-        @Override
-        public void addSearchRows(SearchRow first, SearchRow last) {
-            assert !left.isBatchFull();
-            assert !right.isBatchFull();
-            left.addSearchRows(first, last);
-            right.addSearchRows(first, last);
-        }
-
-        @Override
-        public boolean isBatchFull() {
-            return left.isBatchFull() || right.isBatchFull();
-        }
-
-        @Override
-        public List<Future<Cursor>> find() {
-            // TODO Auto-generated method stub
-            return null;
-        }
-
-        @Override
-        public void reset() {
-            left.reset();
-            right.reset();
-        }
-    }
 }

h2/src/main/org/h2/table/JoinBatch.java

@@ -6,6 +6,7 @@
 package org.h2.table;
 
 import java.util.AbstractList;
+import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.Collections;
 import java.util.List;
@@ -13,10 +14,12 @@ import java.util.concurrent.Future;
 import org.h2.index.Cursor;
 import org.h2.index.IndexCursor;
 import org.h2.index.IndexLookupBatch;
+import org.h2.index.ViewIndex;
 import org.h2.message.DbException;
 import org.h2.result.Row;
 import org.h2.result.SearchRow;
 import org.h2.util.DoneFuture;
+import org.h2.util.New;
 import org.h2.value.Value;
 import org.h2.value.ValueLong;
 
@@ -28,7 +31,6 @@ import org.h2.value.ValueLong;
  * @author Sergi Vladykin
  */
 public final class JoinBatch {
-
     private static final Cursor EMPTY_CURSOR = new Cursor() {
         @Override
         public boolean previous() {
@@ -54,7 +56,11 @@ public final class JoinBatch {
         public String toString() {
             return "EMPTY_CURSOR";
         }
-    }; 
+    };
+
+    private static final Future<Cursor> PLACEHOLDER = new DoneFuture<Cursor>(null);
+
+    private ViewIndexLookupBatch lookupBatchWrapper;
 
     private JoinFilter[] filters;
     private JoinFilter top;
@@ -148,14 +154,16 @@ public final class JoinBatch {
     }
 
     private void start() {
-        // TODO if filters[0].isBatched() then use batching instead of top.filter.getIndexCursor()
         // initialize current row
         current = new JoinRow(new Object[filters.length]);
-        current.updateRow(top.id, top.filter.getIndexCursor(), JoinRow.S_NULL, JoinRow.S_CURSOR);
-
-        // initialize top cursor
-        top.filter.getIndexCursor().find(top.filter.getSession(), top.filter.getIndexConditions());
-
+        if (lookupBatchWrapper == null) {
+            current.updateRow(top.id, top.filter.getIndexCursor(), JoinRow.S_NULL, JoinRow.S_CURSOR);
+            // initialize top cursor
+            top.filter.getIndexCursor().find(top.filter.getSession(), top.filter.getIndexConditions());
+        } else {
+            // we are sub-query and joined to upper level query
+            // TODO setup
+        }
         // we need fake first row because batchedNext always will move to the next row
         JoinRow fake = new JoinRow(null);
         fake.next = current;
@@ -239,7 +247,7 @@ public final class JoinBatch {
                     current = join.find(current);
                 }
                 if (current.row(join.id) != null) {
-                    // either find called or outer join with null row
+                    // either find called or outer join with null-row
                     jfId = join.id;
                     continue;
                 }
@@ -340,13 +348,23 @@ public final class JoinBatch {
         }
     }
 
+    /**
+     * @return Adapter to allow joining to this batch in sub-queries.
+     */
+    public IndexLookupBatch asViewIndexLookupBatch(ViewIndex viewIndex) {
+        if (lookupBatchWrapper == null) {
+            lookupBatchWrapper = new ViewIndexLookupBatch(viewIndex);
+        }
+        return lookupBatchWrapper;
+    }
+
     @Override
     public String toString() {
         return "JoinBatch->\nprev->" + (current == null ? null : current.prev) +
                 "\ncurr->" + current + 
                 "\nnext->" + (current == null ? null : current.next);
     }
-    
+
     /**
      * Table filter participating in batched join.
      */
@@ -404,6 +422,10 @@ public final class JoinBatch {
             return true;
         }
 
+        private List<Future<Cursor>> find() {
+            return lookupBatch.find();
+        }
+
         private JoinRow find(JoinRow current) {
             assert current != null;
 
@@ -655,5 +677,70 @@ public final class JoinBatch {
             return 1;
         }
     }
+    
+    /**
+     * Lookup batch over this join batch for a sub-query or view.
+     */
+    private final class ViewIndexLookupBatch implements IndexLookupBatch {
+        private final ViewIndex viewIndex;
+        private final ArrayList<Future<Cursor>> result = New.arrayList();
+        private boolean findCalled;
+
+        private ViewIndexLookupBatch(ViewIndex viewIndex) {
+            this.viewIndex = viewIndex;
+        }
+
+        @Override
+        public void addSearchRows(SearchRow first, SearchRow last) {
+            if (findCalled) {
+                result.clear();
+                findCalled = false;
+            }
+            viewIndex.setupQueryParameters(viewIndex.getSession(), first, last, null);
+            if (top.collectSearchRows()) {
+                result.add(PLACEHOLDER);
+                if (top.isBatchFull()) {
+                    // TODO
+                }
+            } else {
+                result.add(null);
+            }
+        }
+
+        @Override
+        public boolean isBatchFull() {
+            assert !findCalled;
+            return top.isBatchFull();
+        }
+
+        @Override
+        public List<Future<Cursor>> find() {
+            JoinBatch jb = JoinBatch.this;
+            List<Future<Cursor>> topCursors = top.find();
+            for (int i = 0; i < topCursors.size(); i++) {
+//                jb.setCursor
+                
+                while (jb.next()) {
+                    // collect result
+                }
+            }
+            findCalled = true;
+            return result;
+        }
+
+        @Override
+        public void reset() {
+            findCalled = false;
+            result.clear();
+            JoinBatch.this.reset();
+        }
+    }
+    
+    /**
+     * State of the  
+     */
+    enum State {
+        
+    }
 }
 

h2/src/main/org/h2/table/TableFilter.java

@@ -371,7 +371,10 @@ public class TableFilter implements ColumnResolver {
             jb = join.prepareBatch(id + 1);
         }
         IndexLookupBatch lookupBatch = null;
-        // TODO review the !isAlwaysTopTableFilter condition
+        // the globally top table filter does not need batching, if isAlwaysTopTableFilter is false
+        // then we either not a top table filter or top table filter in a sub-query which is not
+        // top in outer query, thus we need to enable batching here to allow outer query run batched
+        // join against this sub-query
         if (jb == null && select != null && !isAlwaysTopTableFilter(id)) {
             lookupBatch = index.createLookupBatch(this);
             if (lookupBatch != null) {
@@ -384,8 +387,13 @@ public class TableFilter implements ColumnResolver {
             }
             joinBatch = jb;
             joinFilterId = id;
-            // TODO review the !isAlwaysTopTableFilter condition
+            // for globally top table filter we don't need to create lookup batch
+            // currently it will not be used, probably later on it will make sense
+            // to create it to better support X IN (...) conditions, but this needs
+            // to be implemented separately
             if (lookupBatch == null && !isAlwaysTopTableFilter(id)) {
+                // index.createLookupBatch will be called only once because jb can be created only if
+                // lookupBatch is not null from the first call above 
                 lookupBatch = index.createLookupBatch(this);
             }
             jb.register(this, lookupBatch);