Contents: Planning, installing, and configuring Mashup Center : Mashup Center 2.0
Many of the data mashup operators allow you to edit the XPath expressions that are initially generated by the data mashup builder. If you edit an XPath expression, be aware that in Mashup Center 2.0, abbreviated parent path syntax is not allowed.
If you have a version 1.x data mashup that uses the abbreviated parent path syntax, "..
", you must either change the XPath expression or change the data mashup in such a way as to make the parent path step unnecessary.
For example, assume that you have a version 1.x data mashup with a Transform operator that takes the following input entry:
Assume that the Transform operator includes the following user-edited XPath expression:
Figure 1. Version 1.x XPath expression
This XPath expression can be interpreted as "return all <icecream>
elements that are ranked the same as the city Chicago", and would have worked in version 1.x. However, because of the parent path syntax "..
", this expression will return an error in version 2.0. You must change the path to avoid the parent path step. For example, you can change the expression to the following:
Figure 2. Version 2.0 XPath expression
For the sample input entry shown above, this second expression will return the same results as did the version 1.x XPath expression.
Avoid editing XPath expressions as much as possible. For details, see the topic, Tips for better performance in the data mashup builder
in the MashupHub User and Administrator Guide
Parent topic: Understanding changes in the data mashup builder operators : Mashup Center 2.0