Local variables and hidden table-field columns can be declared in 4GL in two types of declaration lists associated with the initialize statement. The syntax below shows these statements. Localcomponent refers to the local variable or hidden column.

Local variables and hidden columns declared within parentheses following the initialize keyword can be accessed by calling frames, which can pass values into them. Local variables and hidden columns declared in the declare section cannot be accessed by other frames.

A 4GL local variable can be of a simple Ingres data type, or a complex user-defined data type (record or array). A hidden column must be of a simple Ingres data type. Local variables of simple and complex types are discussed in the sections that follow.