Hi Sascha
You can do it as often as you like... but bear in mind the load on the server. E.g. if this is a wallboard, you would want a central service to read/cache the data each second, and then hand that cached data out to each wallboard display without repeatedly hitting the DB.
Another method might be to look at the 'enddatetime' field in rtcsqssummary. This appears to be the time/date of the last update to the table. You could use that to work out when the DB will update, e.g. if you read it 4 seconds in a row and the value is the same then it changes on the 5th, updating 5 seconds from then would hit you on next new data.
Aaron
Aaron
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