SQL query to find duplicate records and discount from COUNT

I am using below SQL query to count the records. I would like to discount the duplicate testID after I got the count.

example:

select COUNT(*)  from PRODUCT where CLASS_TYPE = 'test'

​x
 
select COUNT(*)  from PRODUCT where CLASS_TYPE = 'test'​

above query give 5 records

testID
1234-00-01
1234-00-01
1234-00-02
1234-00-02
1111222233

 
testID1234-00-011234-00-011234-00-021234-00-021111222233​

I want to get the count = 5 – duplicate 2 = 3

Is there SQL query I can use to find out the duplicate records, then calculate the final count?

Answer

Please use below query,

select COUNT(distinct testID)  from PRODUCT where CLASS_TYPE = 'test'

 
select COUNT(distinct testID)  from PRODUCT where CLASS_TYPE = 'test'​