User`s guide

Simulating and executing a project
34 Sybase IQ ETL 4.1
To resume simulation from the selected component, select Step from the pop-
up menu. To resume simulation from the current component, select Step from
the toolbar.
Note Selecting Step from the pop-up menu for a component that has not been
processed yet forces all previous components to be stepped first.
Forwarding and backward-forwarding components
The visible flow of the simulation as indicated by the box is straight forward in
many projects. The box is moving from one component to the next. However,
the flow of a project simulation is not necessarily heading strictly into one
direction. The flow of simulation heavily depends on the components used
within the project.
There are forwarding components, which receive a number of records, apply
the transformation to those records, and forward those records (such as the
Data Calculator and the Character Mapper). The number of records that are
being processed in one single step is exclusively determined by the value of the
Read Block Size property of a preceding component.
There are other components that do override the previous Read Block Size
parameter. The Staging component is designed to work on the entire result set
of the data stream (as defined with the Query of the Data Source component).
The component will not process and forward any data records until the entire
result set has been delivered to the IN-port. The Staging component resizes the
amount of records forwarded with the next step by using its own Read Block
Size property. See Chapter 6, “Components” for an explanation of the behavior
of every component during the simulation.
Previewing data from multiple locations
The Preview command is available at every connecting link, every port, and
every component. The
Preview command opens the Preview Content Browser
to display the data currently available at the selected location.
The Preview Content Browser window includes tabs, which allow you to
display multiple previews from multiple locations simultaneously. There are
occasions where it is extremely useful to preview the content of the IN-port and
OUT-port of a component in parallel tabs.