I have an issue with easy charts, and a suggestion to make them better. My problem does not arise from Ignition, but from our OPC server package, Kepware. I am working with them to solve this, but could easily solve it, or patch it in Ignition if it had the flexibility to do so. We upload historical EFM field data from RTUs in the field. Sometimes, we get duplicate data records, a fault of Kepware. Again, we are working with them to resolve this.
I could easily get around this problem by simply using a SQL ‘SELECT DISTINCT’ clause when populating the easy chart, but, Ignition only gives you the ability to manipulate the ‘WHERE’ clause of the underlying SQL statement that populates the chart. This causes a problem for our customers when they select the floppy disk icon to ‘save’ the data to an excel spreadsheet, because all the duplicate records are included.
We would like to propose one of two solutions/enhancements:
that Ignition gives the user complete override of the SQL statement that populates the chart - a check-box that allows the user to enter his own custom SQL statement. Or:
other SQL-based packages, like Crystal Reports, allows for a checkbox that allows the user to ‘SELECT DISTINCT’ - check select distinct records.
Either would resolve our problem and give the developer more control.