There is no UML for showing the flow b/w different technologies. Use any visual representation medium like a flowchart or block diagram in PPT or Visio(anything with Visio gives a feel of being a techie to some ;) )
@OP UML Diagrams are divided in two categories. Structural and Behavior Diagrams. Flows are generally shown using Behavior Diagrams => Activity Diagrams,Sequence Diagrams, Communication diagrams, interaction diagrams ( uml 2) etc.
The flow you are trying to show is generally not shown using UML. You can use some tool like MS Visio, if you really want to show something which is not available in standard UML notation and use your own notations.
You can use Class diagrams to show the static behavior of your system while activity diagram or sequence diagram to represent the dynamic behavior. Also ER diagram could be used to represent your database structure.
show a flow between different technologies(Java,Unix) and Database side(tables)