Ascending order doesn't need any keyword because it’s the default, but you can use the ASC keyword if you want to be explicit.
If you want descending order (as in this example), you use the DESC keyword. The ORDER BY clause then sorts the groups according to that computation.Īs usual, you can use both ascending or descending order with ORDER BY. This effectively counts the number of elements in each group. Then, in the ORDER BY clause, you use the aggregate function COUNT, which counts the number of values in the column of your choice in our example, we count distinct IDs with COUNT(id). The first step is to use the GROUP BY clause to create the groups (in our example, we group by the country column). To sort the selected records by the number of the elements in each group, you use the ORDER BY clause. As of MySQL 8.0. That way, the countries with the greatest number of users will appear at the top. Count relations Can be used inside a top-level include or select Can be used with any query that returns records (including delete, update, and findFirst ). mysql> SELECT pubid,GROUPCONCAT (DISTINCT cateid) -> FROM bookmast -> GROUP BY pubid -> ORDER BY GROUPCONCAT (DISTINCT cateid) ASC +-+-+ pubid GROUPCONCAT (DISTINCT cateid) +-+-+ P003 CA001,CA003 P005 CA001,CA004 P001 CA002,CA004 P0.
But we’ll also sort the groups in descending order by number of users. The MySQL ORDER BY Keyword The ORDER BY keyword is used to sort the result-set in ascending or descending order. Syntax SUBSTR ( string, start, length) OR: SUBSTR ( string FROM start FOR length) Parameter Values Technical Details Works in: From MySQL 4. Note: The SUBSTR () and MID () functions equals to the SUBSTRING () function. COUNT() counts the number of rows, so the query to count your animals looks. Definition and Usage The SUBSTR () function extracts a substring from a string (starting at any position). We’ll group the results by country and count the number of users from each country. Counting the total number of animals you have is the same question as How. But in either case, it will have to do some kind of sort at some point. I have a SQL query to count the number of rating with at least 15 records and then order them by average rating. Our database has a table named user with data in the following columns: id, first_name, last_name, and country. 1 Answer Sorted by: 1 The optimizer might build a hash table - key values of col, value count.
You aggregated data into groups, but you want to sort the records in descending order by the number of elements in the groups.
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