how to find the duplicates in the sql table.

Duplicate sql query

SELECT column_nameFROM table
GROUP BY column_nameHAVING COUNT(*) > 1

Example.

 select inventory_item_id,count(inventory_item_id)
from mtl_system_items_b
where inventory_item_id = 114785
group by inventory_item_id
having count(inventory_item_id) >1   

Here's a handy query for finding duplicates in a table. Suppose you want to find all email addresses in a table that exist more than once:

SELECT email, 
 COUNT(email) AS NumOccurrences
FROM users
GROUP BY email
HAVING ( COUNT(email) > 1 )

You could also use this technique to find rows that occur exactly once:

SELECT email
FROM users
GROUP BY email
HAVING ( COUNT(email) = 1 ) 

simple

------

select job_number, count(*)
from jobsgroup by job_numberhaving count(*) > 1;

another way

===========SELECT *
FROM TABLE AWHERE EXISTS (
  SELECT 1 FROM TABLE
  WHERE COLUMN_NAME = A.COLUMN_NAME
  AND ROWID < A.ROWID)