bool bind_result_t::next_impl()
{
if (_handle->debug)
std::cerr << "MySQL debug: Accessing next row of handle at " << _handle.get() << std::endl;
auto flag = mysql_stmt_fetch(_handle->mysql_stmt);
switch (flag)
{
case 0:
case MYSQL_DATA_TRUNCATED:
{
bool need_to_rebind = false;
for (auto& r : _handle->result_param_meta_data)
{
if (r.len)
{
if (r.bound_is_null)
{
*r.text_buffer = nullptr;
*r.len = 0;
}
else
{
if (r.bound_len > r.bound_text_buffer.size())
{
if (_handle->debug)
std::cerr << "MySQL debug: Need to reallocate buffer at index " << r.index << " for handle at "
<< _handle.get() << std::endl;
need_to_rebind = true;
r.bound_text_buffer.resize(r.bound_len);
MYSQL_BIND& param = _handle->result_params[r.index];
param.buffer = r.bound_text_buffer.data();
param.buffer_length = r.bound_text_buffer.size();
if (mysql_stmt_fetch_column(_handle->mysql_stmt, _handle->result_params.data() + r.index, r.index, 0))
throw sqlpp::exception(std::string("MySQL: Fetch column after reallocate failed: ") +
mysql_stmt_error(_handle->mysql_stmt));
}
*r.text_buffer = r.bound_text_buffer.data();
*r.len = r.bound_len;
}
}
if (r.is_null)
*r.is_null = r.bound_is_null;
}
if (need_to_rebind)
bind_impl();
}
return true;
case 1:
throw sqlpp::exception(std::string("MySQL: Could not fetch next result: ") +
mysql_stmt_error(_handle->mysql_stmt));
case MYSQL_NO_DATA:
return false;
default:
throw sqlpp::exception("MySQL: Unexpected return value for mysql_stmt_fetch()");
}
}
void statement::bind(const string_ref& name, const bind_types_variant& val)
{
bind_impl(name, val);
if (sm_)
{
bindings_ << "['" << name << "', ";
dump_to_ostream vis(bindings_);
val.apply_visitor(vis);
bindings_ << ']';
}
}
auto bind_impl( F&& function , const std::tuple<ARGS...>& args )
{
return bind_impl( std::forward<F>( function ) , args , integer_sequence<tml::pack_size<ARGS...>>{} );
}
