If you’re getting an error message that reads “The function ‘LEAD’ must have an OVER clause with ORDER BY” in SQL Server, it’s probably because you’ve omitted the ORDER BY clause from the OVER clause when using the LEAD() function.
The LEAD() function requires an OVER clause that contains an ORDER BY clause. This error happens when we include the OVER clause but not the ORDER BY clause.
To fix this error, add an ORDER BY clause to the OVER clause.
If you’re getting an error that reads “function mode() does not exist” in PostgreSQL, it could be that you’re using the wrong syntax with this function.
The mode() function requires a WITHIN GROUP clause, and we can get the above error if we remove that clause.
In this case, we can fix the error by adding a valid WITHIN GROUP clause.
If you’re getting an error that reads “The function ‘ROW_NUMBER’ must have an OVER clause” in SQL Server, it’s probably because you’re calling the ROW_NUMBER() function without an OVER clause.
Window functions such as ROW_NUMBER() require an OVER clause (and that clause must have an ORDER BY clause).
To fix this issue, add an OVER clause when calling the ROW_NUMBER() function.
If you’re getting an error that reads “The function ‘DENSE_RANK’ must have an OVER clause with ORDER BY” in SQL Server, it’s probably because you’re calling the DENSE_RANK() function without an ORDER BY clause.
Window functions such as DENSE_RANK() require an OVER clause, and that clause must have an ORDER BY clause. If you’re getting the above error, it’s likely that you’re providing an OVER clause, but you’re omitting the ORDER BY clause.
To fix this error, add an ORDER BY clause to the OVER clause.
There are at least a couple of reasons you might get an error that reads “function nth_value(numeric) does not exist” in PostgreSQL.
It could be that you’re calling the nth_value() function without the correct number of arguments. It could also be that you’re passing the wrong argument type.
To fix this issue, be sure to pass the correct number of arguments, with the correct type.
Continue readingIf you’re getting an error that reads “ERROR: invalid input syntax for type integer” in PostgreSQL, it’s probably because you’re calling the ntile() function with an argument of the wrong data type.
This error can occur when we pass the wrong type to the ntile() function. We can get a different error depending on the type, but this error can occur when we pass a string.
To fix this issue, be sure to pass a positive integer to the function.
Continue readingIn SQL Server, if you’re getting an error that reads “The function ‘PERCENT_RANK’ must have an OVER clause”, it’s because you’re calling the PERCENT_RANK() function without an OVER clause.
The PERCENT_RANK() function requires an OVER clause (and that clause must have an ORDER BY clause).
To fix this issue, be sure to include an OVER clause when calling the PERCENT_RANK() function.
If you’re getting an error that reads “The function ‘ROW_NUMBER’ must have an OVER clause with ORDER BY” in SQL Server, it’s probably because you’re calling the ROW_NUMBER() function without an ORDER BY clause.
Window functions such as ROW_NUMBER() require an OVER clause, and that clause must have an ORDER BY clause. If you’re getting the above error, there’s a good chance you’re providing an OVER clause, but you’re omitting the ORDER BY clause.
To fix this issue, add an ORDER BY clause to the OVER clause when calling the ROW_NUMBER() function.
If you’re getting an error that reads “function ntile() does not exist” in PostgreSQL, it could be that you’re calling the ntile() function without any arguments.
This error message could be a bit misleading. The ntile() function does in fact exist (if you’re using PostgreSQL 8.4 or later), but the error occurs when we don’t provide an argument, or if we provide an argument of the wrong type.
If you’re getting an error that reads “window function nth_value requires an OVER clause” in PostgreSQL, it’s because you’re calling the nth_value() function without an OVER clause.
PostgreSQL requires that you include an OVER clause any time you call a built in nonaggregate window function such as nth_value().
To fix this issue, add an OVER clause to your window function.