Like most other RDBMSs, SQL Server has an AVG() function that returns the average of the values in a group.
Below are examples that demonstrate how the AVG() function works in SQL Server.
Tag: t-sql
How to Fix “The least function requires 1 to 254 arguments” in SQL Server
If you’re getting an error in SQL Server that reads “The least function requires 1 to 254 arguments“, it’s probably because you’re either passing too few or too many arguments to the LEAST() function.
As the error message states, the LEAST() function requires at least 1 argument, and no more than 254 arguments.
To fix this issue, be sure to pass at least 1 argument, and no more than 254 arguments when using the LEAST() function.
How to Force a Guaranteed Minimum Value When Selecting a Column in SQL Server
Suppose you’re trying to query column, but you need to set a minimum value to be returned, even if the column contains values that are less than that minimum. For example, you want a minimum value of 50 to be returned, even if the column contains values that are less than 50.
We can use the GREATEST() function to build such a query.
Introduction to the GREATEST() Function in SQL Server
In SQL Server, the GREATEST() function returns the maximum value from a list of one or more expressions.
The GREATEST() function was introduced in SQL Server 2022 (along with the LEAST() function).
An Overview of the LEAST() Function in SQL Server
SQL Server 2022 introduced the LEAST() and GREATEST() functions, which allow us to get the minimum or maximum value from a list of expressions.
The LEAST() function returns the minimum value from a list of one or more expressions.
Understanding the PERCENTILE_DISC() Function in SQL Server
In SQL Server, PERCENTILE_DISC() is a window function that returns a percentile value based on a discrete distribution of the input column. Basically, it returns the first value in the set whose ordered position is the same or more than the specified fraction.
The output of PERCENTILE_DISC() is equal to a specific column value (unlike the PERCENTILE_CONT() function, which could calculate a value that isn’t in the column).
When we call PERCENTILE_DISC() we specify the percentile to use. It then performs its calculation based on that percentile.
Understanding the PERCENTILE_CONT() Function in SQL Server
In SQL Server, PERCENTILE_CONT() is a window function that calculates a percentile based on a continuous distribution of the column value.
When we call the function, we specify the percentile to use. It then performs its calculation based on that percentile.
Continue readingHow to Use the LEAD() Function in SQL Server
In SQL Server, LEAD() is a window function that allows us to access a value from a later row in the same result set, without the need to perform a self-join.
We specify the row as an offset from the current row. An offset of 1 means it gets the value from the next row, an offset of 2 means two rows forward, and so on.
Introduction to the LAG() Function in SQL Server
In SQL Server, LAG() is a window function that enables us to access a value from a previous row in the same result set, without the need to perform a self-join.
We specify the previous row as an offset from the current row. An offset of 1 means the previous row, an offset of 2 means two rows back, and so on.
How to Use the LAST_VALUE() Function in SQL Server
In SQL Server, the LAST_VALUE() function returns the last value in an ordered set of values.
LAST_VALUE() is a window function that enables us to get a value from the last row of a query result set or partition. This can be useful for when we want to do stuff such as compare a value from the current row with a value in the last row or include it in a calculation.
You may need to explicitly set the window frame if you want LAST_VALUE() to return the actual last value from the partition or result set. That’s because the default window frame ends with the current row. This is covered in the example below.