MCOL-1449. Fix the regression caused by changes in idborderby code for MCOL-1052. Add LIMIT and OFFSET support for group by handler.

dbcon/joblist/limitedorderby.cpp

@@ -77,14 +77,9 @@ void LimitedOrderBy::initialize(const RowGroup& rg, const JobInfo& jobInfo)
         map<uint32_t, uint32_t>::iterator j = keyToIndexMap.find(i->first);
         idbassert(j != keyToIndexMap.end());
 
-        // MCOL-1052 Ordering direction in CSEP differs from
+        // TODO Ordering direction in CSEP differs from
-        // internal direction representation.
+        // internal direction representation. This behavior should be fixed
-        if (i->second)
+        fOrderByCond.push_back(IdbSortSpec(j->second, i->second));
-            fOrderByCond.push_back(IdbSortSpec(j->second, false));
-        else
-            fOrderByCond.push_back(IdbSortSpec(j->second, true));
-
-        //fOrderByCond.push_back(IdbSortSpec(j->second, i->second));
     }
 
     // limit row count info
@@ -182,8 +177,8 @@ void LimitedOrderBy::finalize()
     if (fRowGroup.getRowCount() > 0)
         fDataQueue.push(fData);
 
-    // MCOL-1052 The removed check effectivly disables sorting to happen,
+    // MCOL-1052 The removed check effectively disables sorting,
-    // since fStart = 0;
+    // since fStart = 0 if there is no OFFSET;
     if (true)
     {
         uint64_t newSize = fRowsPerRG * fRowGroup.getRowSize();

dbcon/mysql/ha_calpont_execplan.cpp

@@ -8009,6 +8009,10 @@ int cp_get_group_plan(THD* thd, SCSEP& csep, cal_impl_if::cal_group_info& gi)
     gwi.thd = thd;
     int status = getGroupPlan(gwi, select_lex, csep, gi);
 
+    cerr << "---------------- cp_get_group_plan EXECUTION PLAN ----------------" << endl;
+    cerr << *csep << endl ;
+    cerr << "-------------- EXECUTION PLAN END --------------\n" << endl;
+
     if (status > 0)
         return ER_INTERNAL_ERROR;
     else if (status < 0)
@@ -9877,6 +9881,31 @@ int getGroupPlan(gp_walk_info& gwi, SELECT_LEX& select_lex, SCSEP& csep, cal_gro
                 select_query += ord_cols;
             }
         }
+        // LIMIT and OFFSET are extracted from TABLE_LIST elements. 
+        // All of JOIN-ed tables contain relevant limit and offset. 
+        if (gi.groupByTables->select_lex->select_limit)
+        {
+            csep->limitNum(((Item_int*)gi.groupByTables->select_lex->select_limit)->val_int());
+        }
+
+        if (gi.groupByTables->select_lex->offset_limit)
+        {
+            csep->limitStart(((Item_int*)gi.groupByTables->select_lex->offset_limit)->val_int());
+        }
+
+        //gwi.thd->infinidb_vtable.select_vtable_query.free();
+        //gwi.thd->infinidb_vtable.select_vtable_query.append(select_query.c_str(), select_query.length());
+
+        // We don't currently support limit with correlated subquery
+        if (csep->limitNum() != (uint64_t) - 1 &&
+                gwi.subQuery && !gwi.correlatedTbNameVec.empty())
+        {
+            gwi.fatalParseError = true;
+            gwi.parseErrorText = IDBErrorInfo::instance()->errorMsg(ERR_NON_SUPPORT_LIMIT_SUB);
+            setError(gwi.thd, ER_INTERNAL_ERROR, gwi.parseErrorText, gwi);
+            return ER_CHECK_NOT_IMPLEMENTED;
+        }
+        
     } // ORDER BY processing ends here
 
     if ( gi.groupByDistinct )

dbcon/mysql/ha_calpont_impl.cpp

@@ -5581,14 +5581,19 @@ internal_error:
 */
 /***********************************************************
  * DESCRIPTION:
- * Return a result record for each group_by_handler::next_row() call.
+ * Return a result record for each 
+ * group_by_handler::next_row() call.
  * PARAMETERS:
- *    group_hand - group by handler, that preserves initial table and items lists. .
+ *    group_hand - group by handler, that preserves initial
- *    table - TABLE pointer The table to save the result set in.
+ *  table and items lists. .
+ *    table - TABLE pointer The table to save the result 
+ * set in.
  * RETURN:
  *    0 if success
- *    HA_ERR_END_OF_FILE if the record set has come to an end
+ *    HA_ERR_END_OF_FILE if the record set has come to 
- *    others if something went wrong whilst getting the result set
+ *      an end
+ *    others if something went wrong whilst getting the 
+ *      result set
  ***********************************************************/
 int ha_calpont_impl_group_by_next(ha_calpont_group_by_handler* group_hand, TABLE* table)
 {

utils/windowfunction/idborderby.h

@@ -59,7 +59,8 @@ class  IdbCompare;
 struct IdbSortSpec
 {
     int fIndex;
-    int fAsc;   // <ordering specification> ::= ASC | DESC
+    // TODO There are three ordering specs since 10.2
+    int fAsc;   // <ordering specification> ::= ASC | DESC 
     int fNf;    // <null ordering> ::= NULLS FIRST | NULLS LAST
 
     IdbSortSpec() : fIndex(-1), fAsc(1), fNf(1) {}