# Tag Splitter Querying

**URL:** <https://forum.inductiveautomation.com/t/tag-splitter-querying/108763>\
**Category:** Ignition\
**Created:** [July 22, 2025, 1:27pm UTC](https://forum.inductiveautomation.com/t/tag-splitter-querying/108763 "2025-07-22T13:27:34Z")\
**Posts on this page:** 8\
**Page:** 1

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**Author:** ![nminchin](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/nminchin/32/6911_2.png) [@nminchin](https://forum.inductiveautomation.com/u/nminchin)\
**Post date:** [July 22, 2025, 1:27pm UTC](https://forum.inductiveautomation.com/t/tag-splitter-querying/108763/1 "2025-07-22T13:27:35Z")

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If I query across the First/Second connection limit boundary, i.e. so that both database sources would need to be queried to return all of the results, is this supposed to work?

 ![image](https://us1.discourse-cdn.com/inductiveautomation/original/3X/9/5/95d7d12a86ed4cc848426d95a2d629ca071ceeb6.png)

I have a very simple test where I've generated a single history record each year over 5 years for a tag, then i've duplicated the database and basically made them so that one database has all the data \< 2025 and the other has all the data for 2025. When I try to do a tag history query binding to the tag splitter for the tag across the boundary, it only returns the Second connection's data. If I change the start time to be 2025, then it returns the First connection's data. I can't seem to get it to return data from both connections.

\*\*Query with start = 2022 \*\*

 ![image](https://us1.discourse-cdn.com/inductiveautomation/original/3X/9/2/9281dd10e2a19b6cd64061b500a83faf6db8c964.png)

**Query with start = 2025**

 ![image](https://us1.discourse-cdn.com/inductiveautomation/original/3X/7/2/729c47a3f4238d4492484fb45cf474f1eb9617ce.png)

## First Database

 ![image](https://us1.discourse-cdn.com/inductiveautomation/original/3X/d/2/d297e182d885f6ec01ecff72039b76a4d922ebe3.png)

 ![image](https://us1.discourse-cdn.com/inductiveautomation/original/3X/0/7/07e50bd41ace1d3e9316cb32a7dd0996e979a4ab.png)

## Second Database

 ![image](https://us1.discourse-cdn.com/inductiveautomation/original/3X/7/b/7bf22b73116c93a03ad5ab28972016d824e97135.png)

 ![image](https://us1.discourse-cdn.com/inductiveautomation/original/3X/7/9/7977d277590f1f5e451fddd1d8d139f8b5e82479.png)

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<div class="post-metadata">

**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:** [July 22, 2025, 1:40pm UTC](https://forum.inductiveautomation.com/t/tag-splitter-querying/108763/2 "2025-07-22T13:40:29Z")

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There's no merge. The docs clearly say that one connection will be used or the other. Your attempted architecture is bogus.

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<div class="post-metadata">

**Author:** ![nminchin](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/nminchin/32/6911_2.png) [@nminchin](https://forum.inductiveautomation.com/u/nminchin)\
**Post date:** [July 22, 2025, 1:42pm UTC](https://forum.inductiveautomation.com/t/tag-splitter-querying/108763/3 "2025-07-22T13:42:39Z")

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Well then... that's a bit useless for clients 😕 lucky I'm not actually trying to use it for that! The "second" database is purely for backup. I'm just scripting some data extraction at the moment and was wondering why I was missing this year's data, and that will do it.

Thanks again

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<div class="post-metadata">

**Author:** ![nminchin](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/nminchin/32/6911_2.png) [@nminchin](https://forum.inductiveautomation.com/u/nminchin)\
**Post date:** [July 22, 2025, 1:52pm UTC](https://forum.inductiveautomation.com/t/tag-splitter-querying/108763/4 "2025-07-22T13:52:11Z")

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> [@pturmel](#):
>
> The docs clearly say that one connection will be used or the other

 ![image](https://us1.discourse-cdn.com/inductiveautomation/original/3X/d/7/d7c3b2e31fa3a4940d0f1f2d3791196efb3390c5.png)

I'm not sure if this is the part you're talking about, but I still think the "Limit First Connection Query" description is open to misinterpreting it to mean it would query the first connection for the time that is within the setting, and the second beyond that 🤷‍♂️ That's how I interpreted it when I first read it. I had to squint my eyes to interpret it as you did, although now it kinda seems obvious that was the intention...

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<div class="post-metadata">

**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:** [July 22, 2025, 1:54pm UTC](https://forum.inductiveautomation.com/t/tag-splitter-querying/108763/5 "2025-07-22T13:54:51Z")

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"Queries that go further back execute against the second connection."

Not even a hint of merging. You are engaging in wishful thinking.

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<div class="post-metadata">

**Author:** ![nminchin](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/nminchin/32/6911_2.png) [@nminchin](https://forum.inductiveautomation.com/u/nminchin)\
**Post date:** [July 22, 2025, 1:58pm UTC](https://forum.inductiveautomation.com/t/tag-splitter-querying/108763/6 "2025-07-22T13:58:16Z")

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> [@pturmel](#):
>
> Queries that go further back execute against the second connection.

If there was a clarifying sentence after it would be unmistakable:  
"Queries that go further back execute against the second connection. This also means that queries whose dates span across the limit boundary will execute _only against the second connection_."

@Paul.Scott (not sure if I can still ping you for user manual changes?)

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<div class="post-metadata">

**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:** [July 22, 2025, 2:08pm UTC](https://forum.inductiveautomation.com/t/tag-splitter-querying/108763/7 "2025-07-22T14:08:01Z")

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A manual change that adds the word "only" after "execute" in the sentence I quoted would add clarity. (Not necessary, IMO, but wouldn't hurt.)

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<div class="post-metadata">

**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:** [July 22, 2025, 2:10pm UTC](https://forum.inductiveautomation.com/t/tag-splitter-querying/108763/8 "2025-07-22T14:10:49Z")

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> [@nminchin](#):
>
> that's a bit useless for clients

I disagree. This architecture allows the first connection to be closely pruned to maintain high performance, while the second connection keeps everything. (Or much longer.)