For tables without a single column primary key of type INT or LONG, the unique…

For tables without a single column primary key of type INT or LONG, the unique row id had gaps, which didn't look nice.

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

@@ -140,7 +140,7 @@ public class PageDataIndex extends PageIndex {
                 store.incrementChangeCount();
             }
         }
-        lastKey = Math.max(lastKey, row.getKey() + 1);
+        lastKey = Math.max(lastKey, row.getKey());
     }
 
     public DbException getNewDuplicateKeyException() {
@@ -258,12 +258,11 @@ public class PageDataIndex extends PageIndex {
     }
 
     public Cursor find(Session session, SearchRow first, SearchRow last) {
-        if (first != null || last != null) {
-            // this index is a table scan, must not use it for lookup
-            throw DbException.throwInternalError(getSQL() + " " + first + " " + last);
-        }
+        long from = first == null ? Long.MIN_VALUE : first.getKey();
+        long to = last == null ? Long.MAX_VALUE : last.getKey();
         PageData root = getPage(rootPageId, 0);
-        return root.find(session, Long.MIN_VALUE, Long.MAX_VALUE, isMultiVersion);
+        return root.find(session, from, to, isMultiVersion);
+
     }
 
     /**
@@ -527,4 +526,8 @@ public class PageDataIndex extends PageIndex {
         }
     }
 
+    public boolean isRowIdIndex() {
+        return true;
+    }
+
 }