SQL Exercises: Count how many salesmen each day register orders
SQL Aggregate Functions: Exercise-20 with Solution
From the following table, write a SQL query to count the number of orders based on the combination of each order date and salesperson. Return order date, salesperson id.
Sample table: orders
Sample Solution:
SELECT ord_date,salesman_id,COUNT(*)
FROM orders
GROUP BY ord_date,salesman_id;
Output of the Query:
ord_date salesman_id count 2012-07-27 5001 1 2012-08-17 5007 1 2012-04-25 5001 1 2012-09-10 5002 1 2012-10-05 5002 1 2012-10-10 5003 1 2012-09-10 5005 1 2012-08-17 5003 1 2012-06-27 5002 1 2012-09-10 5001 1 2012-10-05 5001 1 2012-10-10 5006 1
Code Explanation:
The said SQL query that count the number of orders placed on each date by each salesman. The "GROUP BY ord_date, salesman_id" clause groups the rows in the 'orders' table by the "ord_date" and "salesman_id" columns, and the "COUNT()" function counts the number of rows in each group.
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Previous SQL Exercise: Number of non NULL city values for salesmen.
Next SQL Exercise: Calculate the average price of all the products.
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SQL: Tips of the Day
What is the best way to paginate results in SQL Server?
SELECT * FROM ( SELECT ROW_NUMBER() OVER ( ORDER BY OrderDate ) AS RowNum, * FROM Orders WHERE OrderDate >= '1980-01-01' ) AS RowConstrainedResult WHERE RowNum >= 1 AND RowNum < 20 ORDER BY RowNum
Database: SQL Server
Ref: https://bit.ly/3MGrNlk
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