More on Paths

Blog Post created by smohr on Sep 3, 2009

Right now, we have path-context-manner-column as the tuple that locates an item of data.  Let's focus on the first and last (path and column).  To be frank, column grew out of the columns that PI tags return.  Other data sources may not have anything like this.  Would it make more sense to fold "column" into the path syntax for PI points?


Right now, if you provide a list of points (n in number) and a list of columns (m in number), you get n x m results, helpfully labelled "pi:\\server\tag(column)".  If we make the input look like the output, you would no longer have to provide the columns separately and the scheme shrinks to path-context-manner.


The benefits are that you could have a ragged array (e.g., value, max, min, and average for one path and value for another), and future, non-PI sources wouldn't be burdened with a PI-centric concept.  The downside is longer paths.


What do you think?  How would you use the web service?