ReadAtTimeTags

ReadAtTimeTags

The general query structure is as follows:

SELECT

       tagName,

       timestamp ,

       value, --value as a double

       lValue, --value as a long

       sValue, --value as a string

       quality, --numeric opc da quality (0 = bad, >= 64 = uncertain, >= 192 = good)

       squality,   --string quality (good, bad, uncertain)

       historianQuality, --numeric historian quality

       sHistorianQuality --string historian quality (raw, calculated, interpolated, nobound, etc)

FROM

       ctc_fn_PARCdata_ReadAtTimeTags

(

       'Plantname.Sample.1,Plantname.Sample.2' , --tag list. the last parameter passed is the character used to separate the tags

       '10-oct-2010 17:00, 10-oct-2010 18:00, 10-oct-2010 19:00' , --list of times to read. the values will be interpolated at each time according to each tag's interpolation type

       ',' --delimiter in tag list as well as the timestamp list

)

The arguments for the function are:

TagList (string): List of tags for which to get raw data. If there is more than one, use the Delimiter argument.

TimeStamps (string): A delimited and separated list of timestamps for the data to be read at. Use the delimiter defined in the Delimiter argument.

Delimiter (string): The character used to separate/delimit the tags in the TagList argument.

Results come back ordered by tag then by timestamp if no ORDER BY clause is specified.

Sample output: