A field holds a single piece of data, such as a salary,a person's last name, or a timestamp.
For some data types, such as XML, the content may be more "complex", but to Sybase CEP Server it is still a single piece of data.
Because database tables and Sybase CEP windows can be thought of as arranging data in rows and columns, we use the terms "column" and "field" interchangeably.
Note that a field may contain a NULL value to indicate that the value is unknown.