Method prepare_inner

sql/sql_update.cc:3105–3272

*/

bool Sql_cmd_update::prepare_inner(THD *thd)
{
  JOIN *join;
  int err= 0;
  SELECT_LEX *const select_lex = thd->lex->first_select_lex();
  TABLE_LIST *const table_list = select_lex->get_table_list();
  ulonglong select_options= select_lex->options;
  bool free_join= 1;
  DBUG_ENTER("Sql_cmd_update::prepare_inner");

  (void) read_statistics_for_tables_if_needed(thd, table_list);

  THD_STAGE_INFO(thd, stage_init_update);

  if (!multitable)
  {
    if (mysql_handle_derived(lex, DT_INIT))
      DBUG_RETURN(TRUE);
  }

  if (table_list->has_period() && table_list->is_view_or_derived())
  {
     my_error(ER_IT_IS_A_VIEW, MYF(0), table_list->table_name.str);
     DBUG_RETURN(TRUE);
  }

  if (!multitable)
  {
    TABLE_LIST *update_source_table= 0;

    if (((update_source_table=unique_table(thd, table_list,
                                          table_list->next_global, 0)) ||
        table_list->is_multitable()))
    {
      DBUG_ASSERT(update_source_table || table_list->view != 0);
      if (thd->lex->period_conditions.is_set())
      {
        my_error(ER_NOT_SUPPORTED_YET, MYF(0),
                 "updating and querying the same temporal periods table");
        DBUG_RETURN(TRUE);
      }
      if (!table_list->is_multitable() &&
          !processing_as_multitable_update_prohibited(thd))
        multitable= true;
    }
  }

  if(!multitable)
  {
    if (table_list->is_view_or_derived() &&
        select_lex->leaf_tables.elements > 1)
      multitable = true;
  }

  if (!multitable)
  {
    if (lex->ignore)
      lex->set_stmt_unsafe(LEX::BINLOG_STMT_UNSAFE_UPDATE_IGNORE);