In a test at university there was a question; is it possible to use an aggregate function in the SQL WHERE clause. I always thought this isn't possible and I also can't find any example how it wo...
I'm finding a way to aggregate strings from different rows into a single row. I'm looking to do this in many different places, so having a function to facilitate this would be nice. I've tried solu...
2 First and Last do not exist in Sql Server 2005 or 2008, but in Sql Server 2012 there is a First_Value, Last_Value function. I tried to implement the aggregate First and Last for Sql Server 2005 and came to the obstacle that sql server does guarantee the calculation of the aggregate in a defined order.
34 Why can't we use aggregate function in where clause Aggregate functions work on sets of data. A WHERE clause doesn't have access to entire set, but only to the row that it is currently working on. You can of course use HAVING clause:
Mysql / Mariadb also have BIT_AND and BIT_OR aggregate functions which you can apply to columns of boolean values. Postgres has BOOL_AND and BOOL_OR. I think it would give the same result as this suggestion of using MIN or MAX function, but arguably easier to understand the intention.
The SQL GROUP BY clause can be used in a SELECT statement to collect data across multiple records and group the results by one or more columns. In more simple words GROUP BY statement is used in conjunction with the aggregate functions to group the result-set by one or more columns.
I'm working on creating a SQL query that will pull records from a table based on the value of two aggregate functions. These aggregate functions are pulling data from the same table, but with different filter conditions.
The only type of functions you can write in pure T-SQL are scalar and table valued functions. Compare the pages for CREATE AGGREGATE, which only lists CLR style options, with CREATE FUNCTION, which shows T-SQL and CLR options.
What is the difference between scalar-valued, table-valued, and aggregate functions in SQL server? And does calling them from a query need a different method, or do we call them in the same way?
Some database engines like Microsoft Access supports FIRST() as an aggregate function and I was using it in cases I know the column will only have one value in the group. Potentially, the database
