Tag Query with prefixed _

[Former Member]

Why do some results prefix the Tag with "_"?

[salvatore_castro · Accepted solution]

Brian,

It's because the name of the tag starts with an invalid XML character. As a result xMII has to format the name in order to build the XML document properly.

There's a function in the BLS Link Editor called XMLEncodeName() which is what gets called to format the tag to be XML friendly.

Hope this helps.

Sam

[jcgood25]

Brian,

Since this response was sitting in your Inbox prior to your forum post I figured it was worth sharing to the rest of the SDN community:

When you see html results in the browser it is actually the xml results with a stylesheet to turn Rowsets/Rowset/Row into the pretty html table (http://localhost/Illuminator/StyleSheets/IllumRowsetHTML.xsl), and effectively from a query perspective you have two output builders: XML (for xml, html, csv) and binary (for applets).

The '_' character you are seeing is only relevant in the XML output, since your column name (TagName) starts with a non-XML friendly character just like if it would start with a number or any other bogus character like the # sign. If you test your query in XML and look in the output you will see that each data item in the Row nodes substitutes the characters with the underscore, but in the Column section you will see that the real tagname is preserved with the SourceName and Name attributes.

In the binary mode used by the applets this does not happen.

Regards,

Jeremy