How to let the created table visible to current process when using SPI_execute("create table ...")?

When Postmaster starts, I've forked another process AP just as syslogger, bgwritter,...
In the process AP, If I can't find a table, I would create one, the codes are:
            char         * sqlCreate_DM_ =       "create table DM_( ...); ";
            SPI_connect();
            int ret = SPI_execute(sqlCreate_DM_, false, 1);
            SPI_finish();
but after SPI_finish(); I found the created table DM_ is not visible to current process, how to resolve it?
Thanks!