Method modify_record

handlersocket/database.cpp:570–650

}

int
dbcontext::modify_record(dbcallback_i& cb, TABLE *const table,
  const prep_stmt& pst, const cmd_exec_args& args, char mod_op,
  size_t& modified_count)
{
  if (mod_op == 'U') {
    /* update */
    handler *const hnd = table->file;
    uchar *const buf = table->record[0];
    store_record(table, record[1]);
    const prep_stmt::fields_type& rf = pst.get_ret_fields();
    const size_t n = rf.size();
    for (size_t i = 0; i < n; ++i) {
      const string_ref& nv = args.uvals[i];
      uint32_t fn = rf[i];
      Field *const fld = table->field[fn];
      if (nv.begin() == 0) {
	fld->set_null();
      } else {
	fld->set_notnull();
	fld->store(nv.begin(), nv.size(), &my_charset_bin);
      }
    }
    table_vec[pst.get_table_id()].modified = true;
    const int r = hnd->ha_update_row(table->record[1], buf);
    if (r != 0 && r != HA_ERR_RECORD_IS_THE_SAME) {
      return r;
    }
    ++modified_count; /* TODO: HA_ERR_RECORD_IS_THE_SAME? */
  } else if (mod_op == 'D') {
    /* delete */
    handler *const hnd = table->file;
    table_vec[pst.get_table_id()].modified = true;
    const int r = hnd->ha_delete_row(table->record[0]);
    if (r != 0) {
      return r;
    }
    ++modified_count;
  } else if (mod_op == '+' || mod_op == '-') {
    /* increment/decrement */
    handler *const hnd = table->file;
    uchar *const buf = table->record[0];
    store_record(table, record[1]);
    const prep_stmt::fields_type& rf = pst.get_ret_fields();
    const size_t n = rf.size();
    size_t i = 0;
    for (i = 0; i < n; ++i) {
      const string_ref& nv = args.uvals[i];
      uint32_t fn = rf[i];
      Field *const fld = table->field[fn];
      if (fld->is_null() || nv.begin() == 0) {
	continue;
      }
      const long long pval = fld->val_int();
      const long long llv = atoll_nocheck(nv.begin(), nv.end());
      /* TODO: llv == 0? */
      long long nval = 0;
      if (mod_op == '+') {