Function check_view_single_update

sql/sql_insert.cc:128–194

*/

static bool check_view_single_update(List<Item> &fields, List<Item> *values,
                                     TABLE_LIST *view, table_map *map,
                                     bool insert)
{
  /* it is join view => we need to find the table for update */
  List_iterator_fast<Item> it(fields);
  Item *item;
  TABLE_LIST *tbl= 0;            // reset for call to check_single_table()
  table_map tables= 0;

  while ((item= it++))
    tables|= item->used_tables();

  /*
    Check that table is only one
    (we can not rely on check_single_table because it skips some
    types of tables)
  */
  if (my_count_bits(tables) > 1)
    goto error;

  if (values)
  {
    it.init(*values);
    while ((item= it++))
      tables|= item->view_used_tables(view);
  }

  /* Convert to real table bits */
  tables&= ~PSEUDO_TABLE_BITS;

  /* Check found map against provided map */
  if (*map)
  {
    if (tables != *map)
      goto error;
    return FALSE;
  }

  if (view->check_single_table(&tbl, tables, view) || tbl == 0)
    goto error;

  /* view->table should have been set in mysql_derived_merge_for_insert */
  DBUG_ASSERT(view->table);

  /*
    Use buffer for the insert values that was allocated for the merged view.
  */
  tbl->table->insert_values= view->table->insert_values;
  view->table= tbl->table;
  if (!tbl->single_table_updatable())
  {
    if (insert)
      my_error(ER_NON_INSERTABLE_TABLE, MYF(0), view->alias.str, "INSERT");
    else
      my_error(ER_NON_UPDATABLE_TABLE, MYF(0), view->alias.str, "UPDATE");
    return TRUE;
  }