Avoid copying of external result if WITH TIES limit was already applied

h2/src/main/org/h2/command/dml/Insert.java

@@ -267,6 +267,11 @@ public class Insert extends Prepared implements ResultTarget {
         return rowNumber;
     }
 
+    @Override
+    public void limitsWereApplied() {
+        // Nothing to do
+    }
+
     @Override
     public String getPlanSQL() {
         StatementBuilder buff = new StatementBuilder("INSERT INTO ");

h2/src/main/org/h2/command/dml/Select.java

@@ -677,6 +677,7 @@ public class Select extends Query {
                 }
                 result.addRow(row);
             }
+            result.limitsWereApplied();
         }
         if (forUpdateRows != null) {
             topTableFilter.lockRows(forUpdateRows);

h2/src/main/org/h2/result/LocalResult.java

@@ -42,6 +42,7 @@ public class LocalResult implements ResultInterface, ResultTarget {
     private int offset;
     private int limit = -1;
     private boolean withTies;
+    private boolean limitsWereApplied;
     private ResultExternal external;
     private boolean distinct;
     private int[] distinctIndexes;
@@ -381,6 +382,9 @@ public class LocalResult implements ResultInterface, ResultTarget {
     }
 
     private void applyOffsetAndLimit() {
+        if (limitsWereApplied) {
+            return;
+        }
         int offset = Math.max(this.offset, 0);
         int limit = this.limit;
         if (offset == 0 && limit < 0 || rowCount == 0) {
@@ -461,6 +465,11 @@ public class LocalResult implements ResultInterface, ResultTarget {
         return rowCount;
     }
 
+    @Override
+    public void limitsWereApplied() {
+        this.limitsWereApplied = true;
+    }
+
     @Override
     public boolean hasNext() {
         return !closed && rowId < rowCount - 1;

h2/src/main/org/h2/result/ResultTarget.java

@@ -26,4 +26,11 @@ public interface ResultTarget {
      */
     int getRowCount();
 
+    /**
+     * A hint that offset and limit may be ignored by this result because they
+     * were applied during the query. This is useful for WITH TIES clause
+     * because result may contain tied rows above limit.
+     */
+    void limitsWereApplied();
+
 }