# The Sample Mode is manually triggered

**URL:** <https://forum.inductiveautomation.com/t/the-sample-mode-is-manually-triggered/89436>\
**Category:** Ignition\
**Tags:** ignition81\
**Created:** [April 25, 2024, 9:13am UTC](https://forum.inductiveautomation.com/t/the-sample-mode-is-manually-triggered/89436 "2024-04-25T09:13:05Z")\
**Posts on this page:** 3\
**Page:** 1

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**Author:** ![770043297](https://avatars.discourse-cdn.com/v4/letter/7/b9bd4f/32.png) [@770043297](https://forum.inductiveautomation.com/u/770043297)\
**Post date:** [April 25, 2024, 9:13am UTC](https://forum.inductiveautomation.com/t/the-sample-mode-is-manually-triggered/89436/1 "2024-04-25T09:13:05Z")

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### Sample Mode[​](https://docs.inductiveautomation.com/docs/8.1/ignition-modules/tag-historian/configuring-tag-history#sample-mode)

The Sample Mode setting determines how often the Tag History system will check if the tag’s value should be stored to the database using Deadband and Deadband Style settings.

- **On Change** - Ignition will check if the value should be stored to the database each time the tag value changes.
- **Periodic** - Ignition will check if the value should be stored to the database at a specific rate defined by the **Sample Rate** property.
- **Tag Group** - Ignition will check if the value should be stored to the database at the specific rate defined within the Tag Group selected under the **Historical Tag Group** property.

Can I trigger B Tag for storage when A Tag value changes?  
I'm worried that the A tag changes twice and the B Tag value doesn't change so I only store it once

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**Author:** ![Transistor](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/transistor/32/3380_2.png) [@Transistor](https://forum.inductiveautomation.com/u/Transistor)\
**Post date:** [April 25, 2024, 9:30am UTC](https://forum.inductiveautomation.com/t/the-sample-mode-is-manually-triggered/89436/2 "2024-04-25T09:30:00Z")

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> [@770043297](#):
>
> I'm worried that the A tag changes twice and the B Tag value doesn't change so I only store it once

That is the intention of the data history compression.

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**Author:** ![pturmel](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/pturmel/32/3295_2.png) [@pturmel](https://forum.inductiveautomation.com/u/pturmel)\
**Post date:** [April 25, 2024, 12:18pm UTC](https://forum.inductiveautomation.com/t/the-sample-mode-is-manually-triggered/89436/3 "2024-04-25T12:18:53Z")

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If you need **synchronized** storage of values, the tag historian is not the right tool. Use a transaction group (SQL Bridge module) or script an insert to your database.