Fix window functions with order but without frame

h2/src/main/org/h2/expression/aggregate/AbstractAggregate.java

@@ -75,37 +75,39 @@ public abstract class AbstractAggregate extends DataAnalysisOperation {
     protected void getOrderedResultLoop(Session session, HashMap<Integer, Value> result, ArrayList<Value[]> ordered,
             int rowIdColumn) {
         WindowFrame frame = over.getWindowFrame();
-        if (frame == null || frame.isDefault()) {
-            // Aggregate all values before the current row (including)
-            Object aggregateData = createAggregateData();
-            for (Value[] row : ordered) {
-                // Collect values one by one
-                updateFromExpressions(session, aggregateData, row);
-                result.put(row[rowIdColumn].getInt(), getAggregatedValue(session, aggregateData));
+        if (frame == null) {
+            if (over.getOrderBy() == null) {
+                aggregateWholePartition(session, result, ordered, rowIdColumn);
+                return;
             }
         } else if (frame.isFullPartition()) {
-            // Aggregate values from the whole partition
-            Object aggregateData = createAggregateData();
-            for (Value[] row : ordered) {
-                updateFromExpressions(session, aggregateData, row);
+            aggregateWholePartition(session, result, ordered, rowIdColumn);
+            return;
         }
-            // All rows have the same value
-            Value value = getAggregatedValue(session, aggregateData);
-            for (Value[] row : ordered) {
-                result.put(row[rowIdColumn].getInt(), value);
-            }
-        } else {
         // All other types of frames (slow)
         int size = ordered.size();
         for (int i = 0; i < size; i++) {
             Object aggregateData = createAggregateData();
-                for (Iterator<Value[]> iter = frame.iterator(session, ordered, getOverOrderBySort(), i, false); iter
-                        .hasNext();) {
+            for (Iterator<Value[]> iter = WindowFrame.iterator(over, session, ordered, getOverOrderBySort(), i,
+                    false); iter.hasNext();) {
                 updateFromExpressions(session, aggregateData, iter.next());
             }
             result.put(ordered.get(i)[rowIdColumn].getInt(), getAggregatedValue(session, aggregateData));
         }
     }
+
+    private void aggregateWholePartition(Session session, HashMap<Integer, Value> result, ArrayList<Value[]> ordered,
+            int rowIdColumn) {
+        // Aggregate values from the whole partition
+        Object aggregateData = createAggregateData();
+        for (Value[] row : ordered) {
+            updateFromExpressions(session, aggregateData, row);
+        }
+        // All rows have the same value
+        Value value = getAggregatedValue(session, aggregateData);
+        for (Value[] row : ordered) {
+            result.put(row[rowIdColumn].getInt(), value);
+        }
     }
 
     /**

h2/src/main/org/h2/expression/aggregate/Window.java

@@ -224,7 +224,7 @@ public final class Window {
             }
         }
         appendOrderBy(builder, orderBy);
-        if (frame != null && !frame.isDefault()) {
+        if (frame != null) {
             if (builder.charAt(builder.length() - 1) != '(') {
                 builder.append(' ');
             }

h2/src/main/org/h2/expression/aggregate/WindowFrame.java

@@ -192,8 +192,8 @@ public final class WindowFrame {
      * Returns iterator for the specified frame, or default iterator if frame is
      * null.
      *
-     * @param frame
-     *            window frame, or null
+     * @param over
+     *            window
      * @param session
      *            the session
      * @param orderedRows
@@ -207,10 +207,16 @@ public final class WindowFrame {
      *
      * @return iterator
      */
-    public static Iterator<Value[]> iterator(WindowFrame frame, Session session, ArrayList<Value[]> orderedRows,
+    public static Iterator<Value[]> iterator(Window over, Session session, ArrayList<Value[]> orderedRows,
             SortOrder sortOrder, int currentRow, boolean reverse) {
-        return frame != null ? frame.iterator(session, orderedRows, sortOrder, currentRow, reverse)
-                : plainIterator(orderedRows, 0, currentRow, reverse);
+        WindowFrame frame = over.getWindowFrame();
+        if (frame != null) {
+            return frame.iterator(session, orderedRows, sortOrder, currentRow, reverse);
+        }
+        int endIndex = orderedRows.size() - 1;
+        return plainIterator(orderedRows, 0,
+                over.getOrderBy() == null ? endIndex : toGroupEnd(orderedRows, sortOrder, currentRow, endIndex),
+                reverse);
     }
 
     private static Iterator<Value[]> plainIterator(ArrayList<Value[]> orderedRows, int startIndex, int endIndex,
@@ -314,16 +320,6 @@ public final class WindowFrame {
                 && s.compareTo(f) <= 0;
     }
 
-    /**
-     * Returns whether window frame specification can be omitted.
-     *
-     * @return whether window frame specification can be omitted
-     */
-    public boolean isDefault() {
-        return starting.getType() == WindowFrameBoundType.UNBOUNDED_PRECEDING && following == null
-                && exclusion == WindowFrameExclusion.EXCLUDE_NO_OTHERS;
-    }
-
     /**
      * Returns whether window frame specification contains all rows in
      * partition.

h2/src/main/org/h2/expression/aggregate/WindowFunction.java

@@ -345,17 +345,16 @@ public class WindowFunction extends DataAnalysisOperation {
     private void getNth(Session session, HashMap<Integer, Value> result, ArrayList<Value[]> ordered, int rowIdColumn) {
         int size = ordered.size();
         for (int i = 0; i < size; i++) {
-            WindowFrame frame = over.getWindowFrame();
             Value[] row = ordered.get(i);
             int rowId = row[rowIdColumn].getInt();
             Value v;
             switch (type) {
             case FIRST_VALUE:
-                v = getNthValue(WindowFrame.iterator(frame, session, ordered, getOverOrderBySort(), i, false), 0,
+                v = getNthValue(WindowFrame.iterator(over, session, ordered, getOverOrderBySort(), i, false), 0,
                         ignoreNulls);
                 break;
             case LAST_VALUE:
-                v = getNthValue(WindowFrame.iterator(frame, session, ordered, getOverOrderBySort(), i, true), 0,
+                v = getNthValue(WindowFrame.iterator(over, session, ordered, getOverOrderBySort(), i, true), 0,
                         ignoreNulls);
                 break;
             case NTH_VALUE: {
@@ -364,7 +363,7 @@ public class WindowFunction extends DataAnalysisOperation {
                     throw DbException.getInvalidValueException("nth row", n);
                 }
                 n--;
-                Iterator<Value[]> iter = WindowFrame.iterator(frame, session, ordered, getOverOrderBySort(), i,
+                Iterator<Value[]> iter = WindowFrame.iterator(over, session, ordered, getOverOrderBySort(), i,
                         fromLast);
                 v = getNthValue(iter, n, ignoreNulls);
                 break;

h2/src/test/org/h2/test/scripts/functions/aggregate/count.sql

@@ -94,3 +94,13 @@ SELECT I, C, COUNT(I) OVER (PARTITION BY C) CNT FROM
 > 4 2 3
 > 5 2 3
 > rows: 5
+
+SELECT X, COUNT(*) OVER (ORDER BY X) C FROM VALUES (1), (1), (2), (2), (3) V(X);
+> X C
+> - -
+> 1 2
+> 1 2
+> 2 4
+> 2 4
+> 3 5
+> rows: 5

h2/src/test/org/h2/test/scripts/functions/window/nth_value.sql

@@ -219,3 +219,13 @@ SELECT ID, CATEGORY,
 
 DROP TABLE TEST;
 > ok
+
+SELECT I, X, LAST_VALUE(I) OVER (ORDER BY X) L FROM VALUES (1, 1), (2, 1), (3, 2), (4, 2), (5, 3) V(I, X);
+> I X L
+> - - -
+> 1 1 2
+> 2 1 2
+> 3 2 4
+> 4 2 4
+> 5 3 5
+> rows: 5