Oracle Tips and Tricks

Oracle Tips & Tricks fro daily use

Drop all elements in Database

BEGIN
   FOR cur_rec IN (SELECT object_name, object_type
                     FROM user_objects
                    WHERE object_type IN
                             ('TABLE',
                              'VIEW',
                              'PACKAGE',
                              'PROCEDURE',
                              'FUNCTION',
                              'SEQUENCE'
                             ))
   LOOP
      BEGIN
         IF cur_rec.object_type = 'TABLE'
         THEN
            EXECUTE IMMEDIATE    'DROP '
                              || cur_rec.object_type
                              || ' "'
                              || cur_rec.object_name
                              || '" CASCADE CONSTRAINTS';
         ELSE
            EXECUTE IMMEDIATE    'DROP '
                              || cur_rec.object_type
                              || ' "'
                              || cur_rec.object_name
                              || '"';
         END IF;
      EXCEPTION
         WHEN OTHERS
         THEN
            DBMS_OUTPUT.put_line (   'FAILED: DROP '
                                  || cur_rec.object_type
                                  || ' "'
                                  || cur_rec.object_name
                                  || '"'
                                 );
      END;
   END LOOP;
END;
/
-- Source: http://stackoverflow.com/questions/1690404/how-to-drop-all-user-tables

 

COMMIT OR ROLLBACK possible?

When do I need a Commit statement?

All commands that manipulate the data need commit and can be rolled back.
This are the DML (Data Manipulation Language) commands.

Data Manipulation Language (DML) statements are used for managing data within schema objects. Some examples:

  • SELECT - retrieve data from the a database
  • INSERT - insert data into a table
  • UPDATE - updates existing data within a table
  • DELETE - deletes all records from a table, the space for the records remain
  • MERGE - UPSERT operation (insert or update)
  • CALL - call a PL/SQL or Java subprogram
  • EXPLAIN PLAN - explain access path to data
  • LOCK TABLE - control concurrency

Look@: http://www.orafaq.com/faq/what_are_the_difference_between_ddl_dml_and_dcl_commands