SQLTag Real Time Provider (Mysql) bidirectionnal use

Ignition
1

I try to have a bidirectionnal binding of SQLTag :

SQLTag Real Time Provider : Mysql DB

When I write the tag from ignition HMI, it’s OK in sqlt_core
When i write the intvalue and valuechange (datetime = CURRENT_TIMESTAMP()) from sql update with the mysql console,the readed value is ok in the ignition database query browser, but the value is not resfred on the ignition HMI ???

Do I write correctly the good field of sqlt_core ?
is this operation allowed ??
(My ignition gateway is in full read/write communication mode)

Please help :prayer:

2

That should work fine, as long as the tag is configured as a static DB tag. In other words, the tag is a “DB Tag” type (tagtype column = 1, in the sqlt_core table), and its expression mode is set to “none”.

If it’s an OPC tag, writes must be sent through the sqlt_wq table. Note: the tables are described in a white paper that you can find in this thread.

In short, it definitely should be possible. Let me know if your tag type is correct, and we can go from there.

Regards,

3

I check (tagtype column = 1, in the sqlt_core table), and its expression mode is set to “none”.
it’s ok, have you other config to check ?

4

First off, you’re not using the 7.3 beta, right? Because that acts a bit differently (all writes go through the write queue).

If 7.2, perhaps (for the sake of testing) try increasing the “poll overlap” to a higher number, like 10 seconds. Having this number high is not what you want to run forever, but it might help narrow things down. I have to imagine your table doesn’t have much in it, but if for some reason it was taking over 1 second to write/read the row, it might be missed.

A few other things:

  • Is the database on the same machine?
  • If you set configchange to CURRENT_TIMESTAMP, does the tag reload? (you’ll want the tag to be displayed in the designer first to see… or watch the tag load stats in the gateway under Status>SQLTags)

There are a number of people who drive their own SQLTags externally in this manner, so I don’t think there’s anything actually wrong in the software… we just need to track down the missing link! :slight_smile:

Regards,