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Is there any difference between Group By and Distinct

What’s the difference between GROUP BY and DISTINCT in a MySQL query?

Answer 1

Duplicate of

Is there any difference between GROUP BY and DISTINCT

It is already discussed here

If still want to listen here

Well group by and distinct has its own use.

Distinct is used to filter unique records out of the records that satisfy the query criteria.

Group by clause is used to group the data upon which the aggregate functions are fired and the output is returned based on the columns in the group by clause. It has its own limitations such as all the columns that are in the select query apart from the aggregate functions have to be the part of the Group by clause.

So even though you can have the same data returned by distinct and group by clause its better to use distinct. See the below example

select col1,col2,col3,col4,col5,col6,col7,col8,col9 from table group by col1,col2,col3,col4,col5,col6,col7,col8,col9

can be written as

select distinct col1,col2,col3,col4,col5,col6,col7,col8,col9 from table

It makes you life easier when you have more columns in the select list. But at the same time if you need to display sum(col10) along with the above columns than you will have to use Group By. In that case distinct will not work.

eg

select col1,col2,col3,col4,col5,col6,col7,col8,col9,sum(col10) from table group by col1,col2,col3,col4,col5,col6,col7,col8,col9

Hope this helps.