Database, parameter, formula, running total and SQL expression fields have their names surrounded by braces. Database field names are taken from the database. For example:
Database field: {Employee.Last Name}
Parameter, formula, running total, and SQL expression field names are specified when the fields are created.
Parameter fields also includes a question mark: {?my parameter field}.
Formula fields include an at sign: {@another formula}.
Running totals fields include a pound sign: {#my running total}.
SQL expression fields include a percent sign: {%my SQL expression}.
Summary and group name fields look like function calls. However, they are really shorthand notation for a report field.
Sum summary field: Sum({Orders.Order Amount}, {Orders.Ship Via}).
Group name field: GroupName({Orders.Ship Via}).