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Programming Microsoft Access Part II
FIGURE 13-1
A simple query using an expression. Notice that the expression has a name attached to it: ???Buyer Full
Name??™.
The parts of an expression
As the examples in the preceding section demonstrate, expressions can be simple or complex.
Expressions can include a combination of operators, object names, functions, literal values, and
constants.
Remembering that expressions don??™t need to contain all these parts, you should understand each of
the following uniquely identifiable portions of an expression:
Operators: >, =, *, And, Or, Not, Like, and so on.
Operators indicate what type of action (operation) will be performed on one or more elements of
an expression. Generally speaking, operators are either mathematical or Boolean (true/false) in
nature.
Object names: Forms![frmContacts], LastName, Price,
tblProducts.Description
Object names, also known as identifiers, are the actual objects: tables, forms, reports, controls, or
fields.


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