Table Query Fail

Ignition
1

I have a table running a simple query.

SELECT*FROM  alarms_r1
where date between time and time

I noticed while working that the table was encountering an error as shown below.

On: Alarms.Root Container.Table.data
caused by GatewayException: Unable to read response from Gateway.
caused by org.xml.sax.SAXParseException; lineNumber: 31; columnNumber: 43; An invalid XML character (Unicode: 0x1) was found in the element content of the document.

I narrowed it down to 2 db entries that were causing the error.
The entries are of type string, and they contained "PS79 PROGRAM NOT MATCH" and "BG79 PROGRAM NOT MATCH"
When I edited the db and put a space in to make the entries "PS 79 PROGRAM NOT MATCH" and "BG 79 PROGRAM NOT MATCH" the error stopped? What is up with that??

2

According to the error, you had a special Unicode control character in your result: 0x1 - SOH

How was the data entered? Even if it’s a string directly from a PLC you might still need to sanitize it by at least stripping out control codes.

3

It also means that Ignition’s serialization/deserialization of the result dataset via XML failed to accommodate a legal character in a string. Sounds like a bug to me.

4

If the data comes from Ignition first, you can use Python’s strip function to remove any nasty Unicode characters before storing it:

sanitized = original.strip(' \f\t\r\n\00')		# strip out control characters

I encountered this same issue reading strings from Mitsubishi Q-Series PLCs.

5

The string is being logged by a transaction group from an OPC tag originating from a Fanuc OPC server. The error codes come from a Fanuc CNC controller. The error codes are verbatim to the error code/message displayed on the controller itself.

6

What confuses me is I have logged other error codes like "PS125 MACRO STATEMENT FORMAT ERROR" with no issues
the PS125 being the same format as the PS79 that caused an error.