There are several useful queries for Oracle DB:

• select TABLE_NAME from SYS.ALL_TABLES where OWNER=’schema’ – select all tables for given schema
• select USERNAME from SYS.ALL_USERS order by USERNAME – select all schemas
• select VIEW_NAME from SYS.ALL_VIEWS where OWNER=’schema’ order by VIEW_NAME – select all views for given schema
• select OBJECT_NAME, OWNER from SYS.ALL_OBJECTS where UPPER(OBJECT_TYPE) = ‘PACKAGE’ order by OWNER, OBJECT_NAME – select all packages that can be viewed by the current user
• select TRIGGER_NAME, OWNER from SYS.ALL_TRIGGERS order by OWNER, TRIGGER_NAME – select all triggers for the current user
• select INDEX_NAME, TABLE_NAME, TABLE_OWNER from SYS.ALL_INDEXES order by TABLE_OWNER, TABLE_NAME, INDEX_NAME – select all indexes