Use aggregate functions for comparison In addition to using subselects to examine data in related tables, it’s also possible to use an aggregate function in a WHERE clause subselect to make a ...

So I am trying to write an update statement that uses two factors to determine the new value of the field, one of the factors is an aggregate function (COUNT). I get the error: An aggregate may ...

Functions are predefined in SQL and you use them to perform operations on data. They let you do things like aggregating data, formatting strings, extracting dates, and so on.