[PATCH] support ROWNUM in openGauss

Signed-off-by: pufuan <pu.fuan@139.com>

src/common/backend/nodes/copyfuncs.cpp

@@ -2267,6 +2267,20 @@ static Param* _copyParam(const Param* from)
     return newnode;
 }
 
+/*
+ * _copyRownum
+ */
+static Rownum* _copyRownum(const Rownum* from)
+{
+    Rownum* newnode = (Rownum*)makeNode(Rownum);
+
+    COPY_SCALAR_FIELD(rownumcollid);
+    COPY_LOCATION_FIELD(location);
+
+    return newnode;
+}
+
+
 /*
  * _copyAggref
  */
@@ -6011,6 +6025,9 @@ void* copyObject(const void* from)
         case T_Param:
             retval = _copyParam((Param*)from);
             break;
+        case T_Rownum:
+            retval = _copyRownum((Rownum*)from);
+            break;
         case T_Aggref:
             retval = _copyAggref((Aggref*)from);
             break;