From 112ba9f162804adb5e847fa11747cd1499e8075c Mon Sep 17 00:00:00 2001
From: drrtuy <drrtuy@gmail.com>
Date: Wed, 30 Jul 2025 22:36:03 +0000
Subject: [PATCH] feat(rbo,rules,QA): changed to way statistics is collected

---
 dbcon/mysql/ha_mcs_execplan.cpp        | 36 +++++++++++++++++++++++---
 dbcon/mysql/rbo_apply_parallel_ces.cpp | 13 ++++++++--
 2 files changed, 44 insertions(+), 5 deletions(-)

diff --git a/dbcon/mysql/ha_mcs_execplan.cpp b/dbcon/mysql/ha_mcs_execplan.cpp
index b5dec04b0..321671eea 100644
--- a/dbcon/mysql/ha_mcs_execplan.cpp
+++ b/dbcon/mysql/ha_mcs_execplan.cpp
@@ -5207,9 +5207,38 @@ int processFrom(bool& isUnion, SELECT_LEX& select_lex, gp_walk_info& gwi, SCSEP&
 
         // trigger system catalog cache
         if (columnStore)
+        {
           gwi.csc->columnRIDs(
               make_table(table_ptr->db.str, table_ptr->table_name.str, lower_case_table_names), true);
-
+        }
+        else
+        {
+          for (uint j = 0; j < table_ptr->table->s->keys; j++)
+          {
+            // for (uint i = 0; i < table_ptr->table->s->key_info[j].usable_key_parts; i++)
+            {
+              Field* field = table_ptr->table->key_info[j].key_part[0].field;
+              std::cout << "j index " << j << " i column " << 0 << " fieldnr "
+                        << table_ptr->table->key_info[j].key_part[0].fieldnr << " " << field->field_name.str;
+              if (field->read_stats)
+              {
+                auto* histogram = dynamic_cast<Histogram_json_hb*>(field->read_stats->histogram);
+                if (histogram)
+                {
+                  std::cout << " has stats ";
+                  SchemaAndTableName tableName = {field->table->s->db.str,
+                    field->table->s->table_name.str}; 
+                  gwi.tableStatisticsMap[tableName][field->field_name.str] = *histogram;
+                }
+                else
+                {
+                  std::cout << " no stats ";
+                }
+              }
+              std::cout << std::endl;
+            }
+          }
+        }
         string table_name = table_ptr->table_name.str;
 
         // @bug5523
@@ -6307,7 +6336,8 @@ void extractColumnStatistics(Item_field* ifp, gp_walk_info& gwi)
           auto* histogram = dynamic_cast<Histogram_json_hb*>(ifp->field->read_stats->histogram);
           if (histogram)
           {
-            SchemaAndTableName tableName = {ifp->field->table->s->db.str, ifp->field->table->s->table_name.str};
+            SchemaAndTableName tableName = {ifp->field->table->s->db.str,
+                                            ifp->field->table->s->table_name.str};
             auto tableStatisticsMapIt = gwi.tableStatisticsMap.find(tableName);
             if (tableStatisticsMapIt == gwi.tableStatisticsMap.end())
             {
@@ -6418,7 +6448,7 @@ int processSelect(SELECT_LEX& select_lex, gp_walk_info& gwi, SCSEP& csep, vector
       case Item::FIELD_ITEM:
       {
         Item_field* ifp = (Item_field*)item;
-        extractColumnStatistics(ifp, gwi);
+        // extractColumnStatistics(ifp, gwi);
         // Handle * case
         if (ifp->field_name.length && string(ifp->field_name.str) == "*")
         {
diff --git a/dbcon/mysql/rbo_apply_parallel_ces.cpp b/dbcon/mysql/rbo_apply_parallel_ces.cpp
index 6cb5d7638..2dbadf773 100644
--- a/dbcon/mysql/rbo_apply_parallel_ces.cpp
+++ b/dbcon/mysql/rbo_apply_parallel_ces.cpp
@@ -64,7 +64,7 @@ bool someAreForeignTables(execplan::CalpontSelectExecutionPlan& csep)
                      [](const auto& table) { return !table.isColumnstore(); });
 }
 
-bool someForeignTablesHasIndex(execplan::CalpontSelectExecutionPlan& csep, optimizer::RBOptimizerContext& ctx)
+bool someForeignTablesHasStatisticsAndMbIndex(execplan::CalpontSelectExecutionPlan& csep, optimizer::RBOptimizerContext& ctx)
 {
   return std::any_of(
       csep.tableList().begin(), csep.tableList().end(),
@@ -83,7 +83,7 @@ bool parallelCESFilter(execplan::CalpontSelectExecutionPlan& csep, optimizer::RB
   // TODO filter out CSEPs with orderBy, groupBy, having
   // Filter out tables that were re-written.
   // return tables.size() == 1 && !tables[0].isColumnstore() && !tableIsInUnion(tables[0], csep);
-  return someAreForeignTables(csep) && someForeignTablesHasIndex(csep, ctx);
+  return someAreForeignTables(csep) && someForeignTablesHasStatisticsAndMbIndex(csep, ctx);
 }
 
 // This routine produces a new ParseTree that is AND(lowerBand <= column, column <= upperBand)
@@ -210,6 +210,15 @@ std::optional<FilterRangeBounds<T>> populateRangeBounds(execplan::SimpleColumn*
     T currentUpperBound = *(uint32_t*)endBucket->start_value.data();
     bounds.push_back({currentLowerBound, currentUpperBound});
   }
+  for (auto& bucket : columnStatistics.get_json_histogram())
+  {
+    T currentLowerBound = *(uint32_t*)bucket.start_value.data();
+    std::cout << "Bucket: " << currentLowerBound << std::endl;
+  }
+  // auto penultimateBucket = columnStatistics.get_json_histogram().begin() + numberOfUnionUnits * numberOfBucketsPerUnionUnit;
+  // T currentLowerBound = *(uint32_t*)penultimateBucket->start_value.data();
+  // T currentUpperBound = *(uint32_t*)columnStatistics.get_last_bucket_end_endp().data();
+  // bounds.push_back({currentLowerBound, currentUpperBound});
 
   for (auto& bound : bounds)
   {