# Tag change script execution **URL:** \ **Category:** Ignition\ **Tags:** ignition81, scripting\ **Created:** [February 22, 2026, 2:14pm UTC](https://forum.inductiveautomation.com/t/tag-change-script-execution/114112 "2026-02-22T14:14:57Z")\ **Posts on this page:** 7\ **Page:** 2
**Author:** ![lane.duncan](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/lane.duncan/32/83700_2.png) [@lane.duncan](https://forum.inductiveautomation.com/u/lane.duncan)\ **Post date:** [February 24, 2026, 4:55am UTC](https://forum.inductiveautomation.com/t/tag-change-script-execution/114112/21 "2026-02-24T04:55:14Z")
Alternatively show the actual dataset values in the log. ---
**Author:** ![svatsal77](https://avatars.discourse-cdn.com/v4/letter/s/5e9695/32.png) [@svatsal77](https://forum.inductiveautomation.com/u/svatsal77)\ **Post date:** [February 24, 2026, 8:48am UTC](https://forum.inductiveautomation.com/t/tag-change-script-execution/114112/22 "2026-02-24T08:48:41Z")
I am manually doing it by opening the designer and modifying the existing dataset values from tag browser. ---
**Author:** ![svatsal77](https://avatars.discourse-cdn.com/v4/letter/s/5e9695/32.png) [@svatsal77](https://forum.inductiveautomation.com/u/svatsal77)\ **Post date:** [February 24, 2026, 8:49am UTC](https://forum.inductiveautomation.com/t/tag-change-script-execution/114112/23 "2026-02-24T08:49:38Z")
I'm on v 8.1.48 ![image](https://us1.discourse-cdn.com/inductiveautomation/original/3X/e/b/ebe1adf705275517c165b63f5632556da9d3ca70.png) ---
**Author:** ![svatsal77](https://avatars.discourse-cdn.com/v4/letter/s/5e9695/32.png) [@svatsal77](https://forum.inductiveautomation.com/u/svatsal77)\ **Post date:** [February 24, 2026, 8:59am UTC](https://forum.inductiveautomation.com/t/tag-change-script-execution/114112/24 "2026-02-24T08:59:29Z")
```python def valueChanged(tag, tagPath, previousValue, currentValue, initialChange, missedEvents): if not initialChange and currentValue.value != previousValue.value: logger = system.util.getLogger('TagChangeExec_Test') logger.info('Exec') logger.info('initialChange : '+ str(initialChange) + ' currentValue.value : ' + str(currentValue.value)) data = system.dataset.toPyDataSet(currentValue.value) for row in data: logger.info(str(list(row))) ``` ![image](https://us1.discourse-cdn.com/inductiveautomation/original/3X/f/5/f5907d84f79afbf17c25f8c926f154f1f8ad4f37.png) ```python JSON tag { "valueSource": "memory", "eventScripts": [ { "eventid": "valueChanged", "script": "\t\n\tif not initialChange and currentValue.value !\u003d previousValue.value:\n\t\tlogger \u003d system.util.getLogger(\u0027TagChangeExec_Test\u0027)\n\t\tlogger.info(\u0027Exec\u0027)\n\t\tlogger.info(\u0027initialChange : \u0027+ str(initialChange) + \u0027 currentValue.value : \u0027 + str(currentValue.value))\n\t\tdata \u003d system.dataset.toPyDataSet(currentValue.value)\n\t\tfor row in data:\n\t\t\tlogger.info(str(list(row)))" } ], "dataType": "DataSet", "name": "Tag0", "value": "{\"columns\":[{\"name\":\"Col0\",\"type\":\"java.lang.Boolean\"},{\"name\":\"Col1\",\"type\":\"java.lang.String\"}],\"rows\":[[true,\"0\"]]}", "tagType": "AtomicTag" } ``` ---
**Author:** ![lane.duncan](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/lane.duncan/32/83700_2.png) [@lane.duncan](https://forum.inductiveautomation.com/u/lane.duncan)\ **Post date:** [February 24, 2026, 9:52am UTC](https://forum.inductiveautomation.com/t/tag-change-script-execution/114112/25 "2026-02-24T09:52:09Z")
> [@svatsal77](#): > > I am manually doing it by opening the designer and modifying the existing dataset values from tag browser. This is may be your issue. Designer may be writing to the tag twice...although I am unable to duplicate your issue in the 8.3 designer. 8.1 is a little different in regards to datasets, so my test is not a 1:1 comparison to your issue. You should write some actual code on a test button. Do not use the tag editor for testing. This code on my test button in 8.3: ```python def runAction(self, event): import traceback logger = system.util.getLogger("dataset value change test") try: inDataset = system.tag.readBlocking(["[default]Tag0"], 1000)[0].value oldValue = inDataset.getValueAt(0,0) newValue = not oldValue newDataset = system.dataset.setValue(inDataset, 0, 0, newValue) system.tag.writeBlocking(["[default]Tag0"], newDataset, 1000) except: #Log any show stopping errors message = traceback.format_exc() system.perspective.print(message) logger.error(message) ``` ---
**Author:** ![svatsal77](https://avatars.discourse-cdn.com/v4/letter/s/5e9695/32.png) [@svatsal77](https://forum.inductiveautomation.com/u/svatsal77)\ **Post date:** [February 24, 2026, 11:29am UTC](https://forum.inductiveautomation.com/t/tag-change-script-execution/114112/26 "2026-02-24T11:29:56Z")
Yes, I implemented the logic at the button level, and now it executes only once. However, the double execution behavior still surprises me, because it only happens when working with _dataset_ tags. Other tag types do not trigger the script twice when edited directly from the Designer’s Tag Browser. ---
**Author:** ![Nol](https://avatars.discourse-cdn.com/v4/letter/n/8e8cbc/32.png) [@Nol](https://forum.inductiveautomation.com/u/Nol)\ **Post date:** [February 24, 2026, 3:27pm UTC](https://forum.inductiveautomation.com/t/tag-change-script-execution/114112/27 "2026-02-24T15:27:30Z")
So I loaded up 8.1.48 and re-did the identical test I did in 8.3.2 and sure enough it fires twice now, same as OP is seeing. So it does seem like it's a bug related to that version that was fixed between then and 8.3. However it specifically only happens when editing from the tag -editor-, if you go and drill down through the tag browser and change a value there it does not happen twice. ![image](https://us1.discourse-cdn.com/inductiveautomation/original/3X/4/e/4e4914513ba66e8da95730ee73274d4fb24069aa.png) Edit: Looks like the tag editor is just doing some stupid stuff. I did a test where all I did was add a space to a comment in the tag change and it executes 3 times. So, yeah. [Previous page](https://forum.inductiveautomation.com/t/tag-change-script-execution/114112.md?page=1)