Is group by faster than distinct?

SELECT DISTINCT will always be the same, or faster, than a GROUP BY. On some systems (i.e. Oracle), it might be optimized to be the same as DISTINCT for most queries. On others (such as SQL Server), it can be considerably faster.Click to see full answer. Regarding this, is group by faster than distinct SQL Server?GROUP BY and DISTINCT both generate the same query execution plan when no aggregates are used, so there is no appreciable difference in performance in this situation. GROUP BY becomes important when aggregates are used. DISTINCT is just for filtering out duplicate records from query result sets.Subsequently, question is, what is the difference between distinct and group by? Distinct is used to find unique/distinct records where as a group by is used to group a selected set of rows into summary rows by one or more columns or an expression. The functional difference is thus obvious. The group by gives the same result as of distinct when no aggregate function is present. Then, is group by better than distinct? There is no significantly difference between group by and distinct clause except the usage of aggregate functions. Both can be used to distinguish the values but if in performance point of view group by is better. When distinct keyword is used , internally it used sort operation which can be view in execution plan.Can we use distinct in group by?A DISTINCT and GROUP BY usually generate the same query plan, so performance should be the same across both query constructs. GROUP BY should be used to apply aggregate operators to each group. If all you need is to remove duplicates then use DISTINCT.