Ignition 8.1.2 SQL Tags Not Updating After Update From 7.9

Ignition
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Unfortunately I have no idea why this is happening. Can anyone provide any insight?

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Regular queries in the query browser execute fine.

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I would look for something else in that tag group not completing, preventing other tags from executing. Consider moving that tag to its own tag group with the same settings and see if it then executes.

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Thanks. I am running it “Fixed Rate”. I thought that bypassed the tag group. But, I did make an entirely new tag group and it still starts up with the uncertain initial value. It will eventually update, minutes later. If I execute the query in the query browser it executed in way less than a second.

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Something is hogging your tag subsystem’s thread pool. You’ll have to poke around to find it. (I often find scripts with some form of sleep in them when looking at such things for clients.) Also consider moving your query to a gateway timer script.

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Thank you for bailing me out. This is why I love these forums. I will dig into that. For now, moving the query to a gateway event timer script worked. Is there a reason why that is a preferred best practice rather than doing the query on a tag?

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  1. Gateway project scope instead of gateway global scope.
  2. Option for a dedicated thread.
  3. Single event script can run multiple queries in any desired order, writing results to memory tags with any desired timing.
  4. Event scripts can post-process results before writing to tags, relieving the DB of static joins and other lookups. Including using cached lookups.
  5. Event scripts can drive multiple target tags from single, larger queries.
  6. Event scripts can simulate joins across datasources.
  7. Easy parallelism control with separate event scripts.
  8. Even when not using a dedicated thread, gateway events use a different thread pool than tag groups and tag events.

Edit:
9) Tag groups (and v7.9 scan classes) are operationally opaque–very un-fun to troubleshoot.

3 Likes
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Okay I have got that problem resolved. I did find an instance of the “wait” command, but thats resolved. I really don’t want to have to recreate all of these query tags if I don’t have to. Is there someone on the Ignition team that may be able to help me narrow in on what is causing the problem?

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Raise a ticket with support. This forum isn’t an official support channel.

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Done. Thanks. It has been a while since I had to reach out.