Can I use distinct and GROUP BY together?
Well, GROUP BY and DISTINCT have their own use. GROUP BY cannot replace DISTINCT in some situations and DISTINCT cannot take place of GROUP BY. It is as per your choice and situation how you are optimizing both of them and choosing where to use GROUP BY and DISTINCT.
Do you need GROUP BY with distinct?
If you want to group your results, use GROUP BY, if you just want a unique list of a specific column, use DISTINCT. This will give your database a chance to optimise the query for your needs.
Can we use distinct and count together in SQL?
Can I use MySQL COUNT() and DISTINCT together? Yes, you can use COUNT() and DISTINCT together to display the count of only distinct rows. If you do not use DISTINCT, then COUNT() function gives the count of all rows.
Is group by better than distinct?
While DISTINCT better explains intent, and GROUP BY is only required when aggregations are present, they are interchangeable in many cases.
What can I use instead of group by?
select , from , where , union , intersect , minus , distinct , count , and , or , as , between .
Is GROUP BY better than distinct?
How can I get distinct values and counts in SQL?
The COUNT DISTINCT function returns the number of unique values in the column or expression, as the following example shows. SELECT COUNT (DISTINCT item_num) FROM items; If the COUNT DISTINCT function encounters NULL values, it ignores them unless every value in the specified column is NULL.
Will GROUP BY remove duplicates?
5 Answers. GROUP BY does not “remove duplicates”. GROUP BY allows for aggregation. If all you want is to combine duplicated rows, use SELECT DISTINCT.
What is a SQL GROUP BY clause?
The SQL GROUP BY clause is used in collaboration with the SELECT statement to arrange identical data into groups. This GROUP BY clause follows the WHERE clause in a SELECT statement and precedes the ORDER BY clause.
What does group by expression mean?
– Group By means to return each value; – Sum means add up all values for the grouped by fields. Expression means: don’t aggregate on this field, just include a column. with this value. For example, if you type into the Field row: Expr1: 99. and choose Expression, you get a 99 on every row of the query.
What is a group by clause?
GROUP BY clause. A GROUP BY clause, part of a SelectExpression, groups a result into subsets that have matching values for one or more columns. In each group, no two rows have the same value for the grouping column or columns.