There are several ways to delete databases, dbspaces, tables, and indexes (including join indexes) in Sybase Central.
Deleting dbspaces, tables and indexes
Right-click the instance of the object (for example, on the product table in the asiqdemo database)
Select Delete.
Other methods:
Left-click the object
and then click the Delete toolbar button 
Left-click the object and press Alt+E,d.
Use the DROP command in DBISQL. For complete syntax, see the Sybase IQ Reference Manual
