Previously reported problem not the actual problem.
Instead, sqlYOG has simply stopped displaying more than about 200 lines in the table, even when I request to have all entries displayed.
This is only affecting one table, at 23,000 lines not the largest table in the database. I now do not know when this started.
Any ideas why so many lines would not be displayed? I see no obvious pattern in the ones that are displayed.
I should add that this is happening on the server as well as two of my home computers.