how do you count the duplicate records in a table

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how do you count the duplicate records in a table..

Answer / priya

select coloumn_name ,count(*) from table_name
group by coloumn_name
having count(*) > 1;

Is This Answer Correct ?    35 Yes 0 No

how do you count the duplicate records in a table..

Answer / babu

Try this,
select col1,count(col1) from tab1
group by col1 having count(col1)>1;

If you want to delete these duplicate entries, use:
delete from tab1 where col1 in (select a.col1 from
(select col1,count(col1) from tab1
group by col1 having count(col1)>1) a);

Is This Answer Correct ?    18 Yes 1 No

how do you count the duplicate records in a table..

Answer / purushotham

select column,count(1) from a
group by column
having count(1)>1;

Is This Answer Correct ?    7 Yes 1 No

how do you count the duplicate records in a table..

Answer / dev

Hi,
There are many ways to do it.

One of that is ,

select count(0) from tab1 a
where a.rowid > any (select b.rowid from tab1 b where
a.col1 =b.col1);

Is This Answer Correct ?    6 Yes 4 No

how do you count the duplicate records in a table..

Answer / akki julak

select count(empno)-count(distinct(empno)) from emp;

Is This Answer Correct ?    3 Yes 2 No

how do you count the duplicate records in a table..

Answer / ajmal khan

There are many way to count the duplicate row in a table
select count(column_name)-count(distinct(column_name)) from
table_name;

Is This Answer Correct ?    1 Yes 0 No

how do you count the duplicate records in a table..

Answer / suresh a

select sum(count(col1) -1) from emp
group by col1 having count(col1) > 1

Is This Answer Correct ?    2 Yes 2 No

how do you count the duplicate records in a table..

Answer / shalu

select count(*) from table_name group by column1,column2...
having count(*) > 1

Is This Answer Correct ?    2 Yes 2 No

how do you count the duplicate records in a table..

Answer / sravan

Hi here is another way to solve this

SELECT NAME, COUNT(NAME) FROM TABLE_NAME
WHERE NAME IN (SELECT NAME FROM TABLE_NAME
GROUP BY NAME
HAVING COUNT(NAME)>1)
GROUP BY NAME;

thanks

Is This Answer Correct ?    0 Yes 0 No

how do you count the duplicate records in a table..

Answer / satheesh

SELECT COUNT(*)
FROM TABLE A
WHERE ROWID NOT IN (SELECT MAX(ROWID)
FROM TABLE B
WHERE A.COL1 = B.COL1);--UNIQUE COLUMN

Is This Answer Correct ?    0 Yes 0 No

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Hi, I am new in oracle(SQL), could anyone help me in writing a correct SQL. Below is the table structure. Table: Subsc Fields: 1. Sub_no (this field will hold values of subscriber nos, for e.g. S111111, S222222, S333333, S444444, etc.) 2. s_status (this field will hold values for different status of subscriber, for e.g. 'A', 'S', 'C', etc.) 3. cus_id (this field will hold values of bill nos for e.g. 11111111, 22222222, 33333333, 44444444, etc.) Table: Bill Fields: 1. Bill_no this field will hold values of bill nos for e.g. 11111111, 22222222, 33333333, 44444444, etc.) 2. b_status = (this field will hold values for different status of bill for e.g. 'O', 'C', 'S', etc.) Note: 1. The Sub_no is a Primary key of Subsc table. 2. The cus_id is a foreign in Subsc table (referred from Bill_no field of Bill table) 3. The Bill_no field is the Primary key of Bill table. Query A --> I wrote a query to select cus_id/Bill_no which is in status open (b_status = 'O') and having more than two active subscriber (i.e. S_status = 'A') in it ( i.e. more the two subscribers in same bill). select s.cus_id from subsc s where exists (select 1 from bill where bill_no = s.cus_id and b_status = 'O') and s_status = 'A' group by s.cus_id having count(sub_no) = 2 Problem : The above query will give the cus_id (or rather bill_no) which are in open status (b_status ='O) and which are having TWO ACTIVE Subscribers (s_status ='A') in it. However, this query will also lists the cus_id/bill_no which are having more than TWO subscribers in it (but only two subscriber will be in Active status (s_status = 'A') and the others will be in s_status = 'C' or s_status = 'S'. Help needed: I want to write a query which will fetch ONLY the cus_id/bill_no which are in open status (b_status ='O') and which are having ONLY TWO ACTIVE subscribers (s_status ='A') in it. B--> If I include the sub_no in the above query then NO row are returned. select s.cus_id, s.sub_no from subsc s where exists (select 1 from bill where bill_no = s.cus_id and b_status = 'O') and s_status = 'A' group by s.cus_id, s.sub_no having count(sub_no) = 2 Help needed: I want to modify the above query which will fetch ONLY the cus_id/bill_no which are in open status (b_status ='O') and which are having ONLY TWO ACTIVE subscribers (s_status ='A') in it ALONG with the sub_no. Thanks a lot in advance. Regards, Nitin

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