Setting rowcount in select statement and executing the query makes the object explorer refresh showing only a portion of the listed tables. Once this happens, you cannot refersh the object explorer tables tab to bring back all the tables. Even if you swicht to different tabs or database and come back.
Steps to replicate:
1. connect to Sybase server you have and choose any database that has more than 10 tables
2. choose any table in the database with at list 10-15 records (but not very big to avoid long execution time)
3. execute the very simple statement - select * from <table_name> by clicking on (Execute F5)
4. modify the above statement by adding set rowcount 10 - it should like as below
set rowcount 10
select * from <table_name>
5. execute the above statements twice by clicking on (Execute F5)
6. the result of the execution of the query should be first 10 records in the table, but more importantly, the section on the left site under Toad Object Explorer window should show only the first 10 table names in the selected database.