Function alloc_engine_independent_statistics

sql/sql_statistics.cc:2366–2411

*/

static int
alloc_engine_independent_statistics(THD *thd, const TABLE_SHARE *table_share,
                                 TABLE_STATISTICS_CB *stats_cb)
{
  Table_statistics *table_stats= stats_cb->table_stats;
  uint fields= table_share->fields;
  uint keys= table_share->keys;
  uint key_parts= table_share->ext_key_parts;
  Index_statistics *index_stats;
  ulonglong *idx_avg_frequency;
  DBUG_ENTER("alloc_engine_independent_statistics");

  Column_statistics *column_stats;
  if (!multi_alloc_root(&stats_cb->mem_root,
                        &table_stats, sizeof(Table_statistics),
                        &column_stats, sizeof(Column_statistics) * fields,
                        &index_stats, sizeof(Index_statistics) * keys,
                        &idx_avg_frequency,
                        sizeof(*idx_avg_frequency) * key_parts,
                        NullS))
    DBUG_RETURN(1);

  /* Zero variables but not the gaps between them */
  bzero(table_stats, sizeof(Table_statistics));
  bzero((void*) column_stats, sizeof(Column_statistics) * fields);
  bzero(index_stats, sizeof(Index_statistics) * keys);
  bzero(idx_avg_frequency, sizeof(idx_avg_frequency) * key_parts);

  stats_cb->table_stats= table_stats;
  table_stats->columns= table_share->fields;
  table_stats->column_stats= column_stats;
  table_stats->index_stats= index_stats;
  table_stats->idx_avg_frequency= idx_avg_frequency;

  create_min_max_statistical_fields(thd, table_share, stats_cb);

  for (KEY *key_info= table_share->key_info, *end= key_info + keys;
       key_info < end;
       key_info++, index_stats++)
  {
    index_stats->init_avg_frequency(idx_avg_frequency);
    idx_avg_frequency+= key_info->ext_key_parts;
  }
  DBUG_ASSERT(idx_avg_frequency <= table_stats->idx_avg_frequency + key_parts);
  DBUG_RETURN(0);
}


/**