How to check for mutiple rows with same data?

Question

Hi all can anyone advise how do i check mutiple rows with same data?

E.g.

I have 2 rows with following values:

Cola         Colb  Colc
TYPE_APPLE   123   abc
Colb         Colb  Colc
TYPE_APPLE   123   abc

I want to write an SQL query which will not select data of mutiple rows which contain the same data as above. How should I write the query?

Answer 1

DISTINCT will combine identical rows. GROUP BY will combine them and allow you to know which ones had multiples using COUNT(*). To meet your "not select data of multiple rows" requirement you will need to add a HAVING clause. Your query will look something like this:

SELECT cola, colb, colc FROM T1 GROUP BY cola, colb, colc HAVING count(*) = 1;

SQL Fiddle Demonstration

Answer 2

Use this query:

SELECT DISTINCT cola,colb,colc FROM table_name