Drop all user objects in your schema

Use this script to generate the drop statements for everything in your schema. You can then run these statements. 

 This query is non-destructive, though it creates destructive results.

select 'drop sequence ' || sequence_name || ';' from user_sequences
UNION
select 'drop trigger ' || trigger_name || ';' from user_triggers
UNION
select 'drop view' || view_name || ';' from user_views
UNION
select 'drop index' || index_name || ';' from user_indexes
UNION
select 'drop table ' || table_name || ';' from user_tables;