Function check_update_fields

sql/sql_insert.cc:374–433

*/

static int check_update_fields(THD *thd, TABLE_LIST *insert_table_list,
                               List<Item> &update_fields,
                               List<Item> &update_values,
                               bool fields_and_values_from_different_maps,
                               table_map *map)
{
  TABLE *table= insert_table_list->table;
  my_bool UNINIT_VAR(autoinc_mark);
  enum_sql_command sql_command_save= thd->lex->sql_command;

  table->next_number_field_updated= FALSE;

  if (table->found_next_number_field)
  {
    /*
      Unmark the auto_increment field so that we can check if this is modified
      by update_fields
    */
    autoinc_mark= bitmap_test_and_clear(table->write_set,
                                        table->found_next_number_field->
                                        field_index);
  }

  thd->lex->sql_command= SQLCOM_UPDATE;

  /* Check the fields we are going to modify */
  if (setup_fields(thd, Ref_ptr_array(),
                   update_fields, MARK_COLUMNS_WRITE, 0, NULL, 0,
                   THD_WHERE::UPDATE_CLAUSE))
  {
    thd->lex->sql_command= sql_command_save;
    return -1;
  }

  thd->lex->sql_command= sql_command_save;

  if (insert_table_list->is_view() &&
      insert_table_list->is_merged_derived() &&
      check_view_single_update(update_fields,
                               fields_and_values_from_different_maps ?
                               (List<Item>*) 0 : &update_values,
                               insert_table_list, map, false))
    return -1;

  if (table->default_field)
    table->mark_default_fields_for_write(FALSE);

  if (table->found_next_number_field)
  {
    if (bitmap_is_set(table->write_set,
                      table->found_next_number_field->field_index))
      table->next_number_field_updated= TRUE;

    if (autoinc_mark)
      bitmap_set_bit(table->write_set,
                     table->found_next_number_field->field_index);
  }