Concatenate multiple result rows of one column into one, group by another column [duplicate]
This question already has answers here: How to concatenate strings of a string field in a PostgreSQL ‘group by’ query? (14 answers) Closed … Read more
aggregate-functions
The SQL OVER() clause – when and why is it useful?
USE AdventureWorks2008R2; GO SELECT SalesOrderID, ProductID, OrderQty ,SUM(OrderQty) OVER(PARTITION BY SalesOrderID) AS ‘Total’ ,AVG(OrderQty) OVER(PARTITION BY SalesOrderID) AS ‘Avg’ ,COUNT(OrderQty) OVER(PARTITION BY SalesOrderID) … Read more
Function to Calculate Median in SQL Server
According to MSDN, Median is not available as an aggregate function in Transact-SQL. However, I would like to find out whether it is … Read more
Reason for Column is invalid in the select list because it is not contained in either an aggregate function or the GROUP BY clause [duplicate]
This question already has answers here: GROUP BY / aggregate function confusion in SQL (5 answers) Closed 2 years ago. I got an … Read more
Apply multiple functions to multiple groupby columns
The docs show how to apply multiple functions on a groupby object at a time using a dict with the output column names … Read more
must appear in the GROUP BY clause or be used in an aggregate function
I have a table that looks like this caller ‘makerar’ cname | wmname | avg ——–+————-+———————— canada | zoro | 2.0000000000000000 spain | … Read more
SQL Server: Difference between PARTITION BY and GROUP BY
I’ve been using GROUP BY for all types of aggregate queries over the years. Recently, I’ve been reverse-engineering some code that uses PARTITION … Read more
SQL select only rows with max value on a column [duplicate]
Want to improve this post? Provide detailed answers to this question, including citations and an explanation of why your answer is correct. without … Read more