In a main program I have a 20MB table that I write to a Shared Memory Table to process in 4 batches - each batch processing a quarter of data. Within each batch I keep track of processing error messages. I want to know how I can append the error messages back to a shared memory table once each batch finishes. It should be possible to lock the shared memory area for write until it's done and the other batches can just wait for a second if the Shared Memory Area is locked at the time. However, my biggest problem is that the Shared Memory Tables are cleared when I ATTACH_FOR_WRITE( ).
How can I apply changes to Shared Memory Tables without wiping all data contained?