Bug#17909699: WRONG RESULTS WITH PARTITION BY LIST COLUMNS()

Typo leading to not including the last list values (partition).

Also improved pruning to skip last partition if not used.

rb#4762 approved by Aditya and Marko.

1 files changed, 22 insertions, 17 deletions

diff --git a/sql/sql_partition.cc b/sql/sql_partition.cc
index e2ff4d07f1a..d7d362dbdfb 100644
--- a/sql/sql_partition.cc
+++ b/sql/sql_partition.cc
@@ -3304,19 +3304,28 @@ uint32 get_partition_id_cols_list_for_endpoint(partition_info *part_info,
   uint num_columns= part_info->part_field_list.elements;
   uint list_index;
   uint min_list_index= 0;
+  int cmp;
+  /* Notice that max_list_index = last_index + 1 here! */
   uint max_list_index= part_info->num_list_values;
   DBUG_ENTER("get_partition_id_cols_list_for_endpoint");
 
   /* Find the matching partition (including taking endpoint into account). */
   do
   {
-    /* Midpoint, adjusted down, so it can never be > last index. */
+    /* Midpoint, adjusted down, so it can never be >= max_list_index. */
     list_index= (max_list_index + min_list_index) >> 1;
-    if (cmp_rec_and_tuple_prune(list_col_array + list_index*num_columns,
-                                nparts, left_endpoint, include_endpoint) > 0)
+    cmp= cmp_rec_and_tuple_prune(list_col_array + list_index*num_columns,
+                                 nparts, left_endpoint, include_endpoint);
+    if (cmp > 0)
+    {
       min_list_index= list_index + 1;
+    }
     else
+    {
       max_list_index= list_index;
+      if (cmp == 0)
+        break;
+    }
   } while (max_list_index > min_list_index);
   list_index= max_list_index;
 
@@ -3333,12 +3342,10 @@ uint32 get_partition_id_cols_list_for_endpoint(partition_info *part_info,
                                            nparts, left_endpoint,
                                            include_endpoint)));
 
-  if (!left_endpoint)
-  {
-    /* Set the end after this list tuple if not already after the last. */
-    if (list_index < part_info->num_parts)
-      list_index++;
-  }
+  /* Include the right endpoint if not already passed end of array. */
+  if (!left_endpoint && include_endpoint && cmp == 0 &&
+      list_index < part_info->num_list_values)
+    list_index++;
 
   DBUG_RETURN(list_index);
 }
@@ -7493,15 +7500,13 @@ static int cmp_rec_and_tuple_prune(part_column_list_val *val,
   field= val->part_info->part_field_array + n_vals_in_rec;
   if (!(*field))
   {
-    /*
-      Full match, if right endpoint and not including the endpoint,
-      (rec < part) return lesser.
-    */
-    if (!is_left_endpoint && !include_endpoint)
-      return -4;
+    /* Full match. Only equal if including endpoint. */
+    if (include_endpoint)
+      return 0;
 
-    /* Otherwise they are equal! */
-    return 0;
+    if (is_left_endpoint)
+      return +4;     /* Start of range, part_tuple < rec, return higher. */
+    return -4;     /* End of range, rec < part_tupe, return lesser. */
   }
   /*
     The prefix is equal and there are more partition columns to compare.