This question is asked more times than one would imagine.
Question: How to detect duplicates in a table?
Answer:
There are multiple ways of doing things. Here are some of them.
Use of group by
select keys, count(*) from mytable
group by keys
having count(*) > 1
For Example:
SQL> select * from t1;
         A          B
———- ———-
         1          1
         1          2
         1          1
         1          3
         […]

Numbers to words!!!

December 10, 2006 | Leave a Comment

A simple way of spelling out numbers to words. This could be handy for printing reciepts, cheques etc.
KDE>select to_char( to_date( abs(&num),’J'),’Jsp’) “NUMBER TO TEXT” from dual
  2  /
Enter value for num: 345
old   1: select to_char( to_date( abs(&num),’J'),’Jsp’) “NUMBER TO TEXT” from dual
new   1: select to_char( to_date( abs(345),’J'),’Jsp’) “NUMBER TO TEXT” from dual
NUMBER TO TEXT
————————
Three Hundred […]

Audit DDL Changes

December 10, 2006 | Leave a Comment

Here is a way of keeping track of all the changes made to a schema by DDL statements.
DROP TRIGGER DDL_CHANGE_TRACKER
/
DROP TABLE   dll_audit_log
/
CREATE TABLE ddl_change_tracker (
   stamp     DATE,
   username  VARCHAR2(30),
   osuser    VARCHAR2(30),
   machine   VARCHAR2(30),
   terminal  VARCHAR2(30),
   operation VARCHAR2(30),
   objtype   VARCHAR2(30),
   objname   VARCHAR2(30))
/
CREATE OR REPLACE TRIGGER audit_ddl_changes
   AFTER create OR drop OR alter
      ON KIRTAN.SCHEMA
BEGIN
  INSERT INTO […]