# \[bug-15295\]system.dataset.appendDataset converting "null" values to 0

**URL:** <https://forum.inductiveautomation.com/t/bug-15295-system-dataset-appenddataset-converting-null-values-to-0/29429>\
**Category:** Ignition\
**Created:** [October 27, 2019, 6:18pm UTC](https://forum.inductiveautomation.com/t/bug-15295-system-dataset-appenddataset-converting-null-values-to-0/29429 "2019-10-27T18:18:40Z")\
**Posts on this page:** 9\
**Page:** 1

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**Author:** ![brian.ankeny](https://avatars.discourse-cdn.com/v4/letter/b/f04885/32.png) [@brian.ankeny](https://forum.inductiveautomation.com/u/brian.ankeny)\
**Post date:** [October 27, 2019, 6:18pm UTC](https://forum.inductiveautomation.com/t/bug-15295-system-dataset-appenddataset-converting-null-values-to-0/29429/1 "2019-10-27T18:18:40Z")

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In my application I need to have null values in a dataset column (of type double). This dataset comprised of several other combined datasets (with identical column formats). I have verified that each of the individual datasets correctly have the null values in them but once they are combined using system.dataset.appendDataset, only the data from the first dataset retains its null values. The rest of the data (from the appended datasets) have the null values converted to 0 (this is bad as the values may not actually be 0 at that time).

Has anyone else seen this? Is this a bug?

I am using version 7.9.10

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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:** [October 27, 2019, 6:21pm UTC](https://forum.inductiveautomation.com/t/bug-15295-system-dataset-appenddataset-converting-null-values-to-0/29429/2 "2019-10-27T18:21:49Z")

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Sounds like a bug.

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<div class="post-metadata">

**Author:** ![brian.ankeny](https://avatars.discourse-cdn.com/v4/letter/b/f04885/32.png) [@brian.ankeny](https://forum.inductiveautomation.com/u/brian.ankeny)\
**Post date:** [October 27, 2019, 6:28pm UTC](https://forum.inductiveautomation.com/t/bug-15295-system-dataset-appenddataset-converting-null-values-to-0/29429/3 "2019-10-27T18:28:06Z")

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Thanks Phil! Do you by chance know the ‘official’ way to report possible bugs?

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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:** [October 27, 2019, 8:34pm UTC](https://forum.inductiveautomation.com/t/bug-15295-system-dataset-appenddataset-converting-null-values-to-0/29429/4 "2019-10-27T20:34:15Z")

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Uhm, [support](https://support.inductiveautomation.com/)?

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**Author:** ![paul-griffith](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/paul-griffith/32/37249_2.png) [@paul-griffith](https://forum.inductiveautomation.com/u/paul-griffith)\
**Post date:** [October 28, 2019, 3:37pm UTC](https://forum.inductiveautomation.com/t/bug-15295-system-dataset-appenddataset-converting-null-values-to-0/29429/5 "2019-10-28T15:37:56Z")

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Yep, it’s a bug. We’re using our never-returns-null coercion function. Whoops. One-line fix 🙂

EDIT: I’ve filed the ticket, so no need to contact support.

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<div class="post-metadata">

**Author:** ![brian.ankeny](https://avatars.discourse-cdn.com/v4/letter/b/f04885/32.png) [@brian.ankeny](https://forum.inductiveautomation.com/u/brian.ankeny)\
**Post date:** [October 30, 2019, 10:41pm UTC](https://forum.inductiveautomation.com/t/bug-15295-system-dataset-appenddataset-converting-null-values-to-0/29429/6 "2019-10-30T22:41:30Z")

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Thanks!

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<div class="post-metadata">

**Author:** ![awalker](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/awalker/32/6874_2.png) [@awalker](https://forum.inductiveautomation.com/u/awalker)\
**Post date:** [November 11, 2019, 4:46pm UTC](https://forum.inductiveautomation.com/t/bug-15295-system-dataset-appenddataset-converting-null-values-to-0/29429/7 "2019-11-11T16:46:13Z")

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This issue was fixed in the 8.0.7 nightly build that was uploaded today (11/11).

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<div class="post-metadata">

**Author:** ![brian.ankeny](https://avatars.discourse-cdn.com/v4/letter/b/f04885/32.png) [@brian.ankeny](https://forum.inductiveautomation.com/u/brian.ankeny)\
**Post date:** [November 19, 2019, 2:26pm UTC](https://forum.inductiveautomation.com/t/bug-15295-system-dataset-appenddataset-converting-null-values-to-0/29429/8 "2019-11-19T14:26:48Z")

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Thank you. Will there be a solution released for 7.9?

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<div class="post-metadata">

**Author:** ![paul-griffith](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/paul-griffith/32/37249_2.png) [@paul-griffith](https://forum.inductiveautomation.com/u/paul-griffith)\
**Post date:** [November 19, 2019, 4:22pm UTC](https://forum.inductiveautomation.com/t/bug-15295-system-dataset-appenddataset-converting-null-values-to-0/29429/9 "2019-11-19T16:22:34Z")

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We don’t currently plan to backport, and it’s missed the cutoff for 7.9.13 regardless. You could get in contact with support and they can file a ticket to request a backport, though it’ll probably be faster to just make a script to do it yourself - it’s not a very complex operation - basically just a few loops.