I have been reading over these news groups and have come across some information that I would like clarification on.
In one group it was mentioned that it is possible to detect if the communications is lost between your two programs and a remote SQL connection. Could you elaborate on how this would be done?
Referencing number 1, lets say the communications is lost and your software has detected it, I am assuming that the best approach would be to have the data logged to the local MySQL database then when communications is re-established push this data over to the main SQL server. Would this be a correct assumption?
Is it more difficult to detect the loss of communications or the re-establisment of communication to the SQL server?
Do you have any examples of best line approaches for doing this?
Now onto the database connections issues:
In the databases that Factory SQL creates there is usually a key column with the _NDX ending to the name. Is this created by the Factory SQL program?
Can this column be used as the key in looking up or retrieving information from a database?
I ask these question because I need a good steady key column for two of my databases. At first I had thought of using a number being sent from the PLC, but this proved to be a problem if communications to the PLC was lost. So my next attempt was to use the ID number comming right from KepServer, however this has proven to be a slight problem in that it is a string not an integer. If it were an integer it would be real easy. So I thought well why not try using the _NDX column but I first needed to know where that information was comming from and who created it. Or if you have a better approach I would greatly appreciate hearing any insight.
Now about screen numbering and securing.
Lets say one starts a new project. They get partway into the project and realize that the default startup screen they created is not the one they want to use, they would rather use another screen as the default startup screen. Can this be changed rather easily? I did read in one of these groups that it could be changed but if you made any changes to your screens the software would default back to the origional choosen one. I am unsure the dating of the post so I dont know if this is something that has been fixed or is being worked on or what so I thought I would ask for an update.
Thank you and have a great day.