Invoking Components

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You can invoke an RDMI component from a USoft SQL context by using one of two constructs:

The USoft-proprietary INVOKE keyword.

Function call syntax.

Either way, the RDMI call may appear in a number of different contexts, for example:

As an independent statement.

In a nested manner, in association with another INVOKE clause.

In association with a SELECT clause.

In a WHERE condition.

In the output list of a SELECT statement.

In a subquery.

In general, there are two different ways to access a component's functionality:

By calling a method of the component.

By calling a query protocol of the component.

The combination of all these options gives you many different constructs to choose from. This help topic shows some possibilities without being exhaustive.

collapseIndependent INVOKE statements
collapseINVOKE in a SELECT output list
collapseINVOKE as a subquery in a SET or WHERE clause
collapseFunction call syntax