Merge 10.0 into 10.1

5 files changed, 74 insertions, 9 deletions

diff --git a/sql/opt_range.cc b/sql/opt_range.cc
index f3740a08fc6..41d74611abc 100644
--- a/sql/opt_range.cc
+++ b/sql/opt_range.cc
@@ -2734,14 +2734,17 @@ bool create_key_parts_for_pseudo_indexes(RANGE_OPT_PARAM *param,
 {
   Field **field_ptr;
   TABLE *table= param->table;
+  partition_info *part_info= NULL;
+  #ifdef WITH_PARTITION_STORAGE_ENGINE
+    part_info= table->part_info;
+  #endif
   uint parts= 0;
 
   for (field_ptr= table->field; *field_ptr; field_ptr++)
   {
-    Column_statistics* col_stats= (*field_ptr)->read_stats;
-    if (bitmap_is_set(used_fields, (*field_ptr)->field_index)
-       && col_stats && !col_stats->no_stat_values_provided()
-       && !((*field_ptr)->type() == MYSQL_TYPE_GEOMETRY))
+    Field *field= *field_ptr;
+    if (bitmap_is_set(used_fields, field->field_index) &&
+        is_eits_usable(field))
       parts++;
   }
 
@@ -2759,12 +2762,10 @@ bool create_key_parts_for_pseudo_indexes(RANGE_OPT_PARAM *param,
   uint max_key_len= 0;
   for (field_ptr= table->field; *field_ptr; field_ptr++)
   {
-    if (bitmap_is_set(used_fields, (*field_ptr)->field_index))
+    Field *field= *field_ptr;
+    if (bitmap_is_set(used_fields, field->field_index))
     {
-      Field *field= *field_ptr;
-      Column_statistics* col_stats= field->read_stats;
-      if (field->type() == MYSQL_TYPE_GEOMETRY ||
-           !col_stats || col_stats->no_stat_values_provided())
+      if (!is_eits_usable(field))
         continue;
 
       uint16 store_length;
diff --git a/sql/partition_info.cc b/sql/partition_info.cc
index df0a733f121..74a1c2a267a 100644
--- a/sql/partition_info.cc
+++ b/sql/partition_info.cc
@@ -3143,6 +3143,23 @@ void partition_info::print_debug(const char *str, uint *value)
     DBUG_PRINT("info", ("parser: %s", str));
   DBUG_VOID_RETURN;
 }
+
+bool partition_info::field_in_partition_expr(Field *field) const
+{
+  uint i;
+  for (i= 0; i < num_part_fields; i++)
+  {
+    if (field->eq(part_field_array[i]))
+      return TRUE;
+  }
+  for (i= 0; i < num_subpart_fields; i++)
+  {
+    if (field->eq(subpart_field_array[i]))
+      return TRUE;
+  }
+  return FALSE;
+}
+
 #else /* WITH_PARTITION_STORAGE_ENGINE */
  /*
    For builds without partitioning we need to define these functions
diff --git a/sql/partition_info.h b/sql/partition_info.h
index b271ff08e82..0f38c87dd4e 100644
--- a/sql/partition_info.h
+++ b/sql/partition_info.h
@@ -384,6 +384,7 @@ private:
   bool is_full_part_expr_in_fields(List<Item> &fields);
 public:
   bool has_unique_name(partition_element *element);
+  bool field_in_partition_expr(Field *field) const;
 };
 
 uint32 get_next_partition_id_range(struct st_partition_iter* part_iter);
diff --git a/sql/sql_statistics.cc b/sql/sql_statistics.cc
index 739930f46fc..7d73a894bdc 100644
--- a/sql/sql_statistics.cc
+++ b/sql/sql_statistics.cc
@@ -30,6 +30,7 @@
 #include "opt_range.h"
 #include "my_atomic.h"
 #include "sql_show.h"
+#include "sql_partition.h"
 
 /*
   The system variable 'use_stat_tables' can take one of the
@@ -3722,6 +3723,22 @@ void set_statistics_for_table(THD *thd, TABLE *table)
     (use_stat_table_mode <= COMPLEMENTARY ||
      !table->stats_is_read || read_stats->cardinality_is_null) ?
     table->file->stats.records : read_stats->cardinality;
+
+  /*
+    For partitioned table, EITS statistics is based on data from all partitions.
+
+    On the other hand, Partition Pruning figures which partitions will be
+    accessed and then computes the estimate of rows in used_partitions.
+
+    Use the estimate from Partition Pruning as it is typically more precise.
+    Ideally, EITS should provide per-partition statistics but this is not
+    implemented currently.
+  */
+  #ifdef WITH_PARTITION_STORAGE_ENGINE
+    if (table->part_info)
+      table->used_stat_records= table->file->stats.records;
+  #endif
+
   KEY *key_info, *key_info_end;
   for (key_info= table->key_info, key_info_end= key_info+table->s->keys;
        key_info < key_info_end; key_info++)
@@ -4037,3 +4054,31 @@ bool is_stat_table(const char *db, const char *table)
   }
   return false;
 }
+
+/*
+  Check wheter we can use EITS statistics for a field or not
+
+  TRUE : Use EITS for the columns
+  FALSE: Otherwise
+*/
+
+bool is_eits_usable(Field *field)
+{
+  partition_info *part_info= NULL;
+  #ifdef WITH_PARTITION_STORAGE_ENGINE
+    part_info= field->table->part_info;
+  #endif
+  /*
+    (1): checks if we have EITS statistics for a particular column
+    (2): Don't use EITS for GEOMETRY columns
+    (3): Disabling reading EITS statistics for columns involved in the
+         partition list of a table. We assume the selecticivity for
+         such columns would be handled during partition pruning.
+  */
+  Column_statistics* col_stats= field->read_stats;
+  if (col_stats && !col_stats->no_stat_values_provided() &&        //(1)
+      field->type() != MYSQL_TYPE_GEOMETRY &&                      //(2)
+      (!part_info || !part_info->field_in_partition_expr(field)))  //(3)
+    return TRUE;
+  return FALSE;
+}
diff --git a/sql/sql_statistics.h b/sql/sql_statistics.h
index d30691c32f0..6530c2d6c8f 100644
--- a/sql/sql_statistics.h
+++ b/sql/sql_statistics.h
@@ -112,6 +112,7 @@ double get_column_range_cardinality(Field *field,
                                     key_range *max_endp,
                                     uint range_flag);
 bool is_stat_table(const char *db, const char *table);
+bool is_eits_usable(Field* field);
 
 class Histogram
 {