# Block Transaction Group Duplicates Even When Rows Do Not Change

**URL:** <https://forum.inductiveautomation.com/t/block-transaction-group-duplicates-even-when-rows-do-not-change/25253>\
**Category:** Ignition\
**Tags:** ignition79\
**Created:** [May 23, 2019, 2:22am UTC](https://forum.inductiveautomation.com/t/block-transaction-group-duplicates-even-when-rows-do-not-change/25253 "2019-05-23T02:22:49Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![19tb21](https://avatars.discourse-cdn.com/v4/letter/1/0ea827/32.png) [@19tb21](https://forum.inductiveautomation.com/u/19tb21)\
**Post date:** [May 23, 2019, 2:22am UTC](https://forum.inductiveautomation.com/t/block-transaction-group-duplicates-even-when-rows-do-not-change/25253/1 "2019-05-23T02:22:49Z")

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Hello, I am having an issue with block transaction groups. I select “Table Action” option “insert changed rows” and the transaction group writes duplicate rows to the DB. The rows are not changing. I can do the same thing with scripting if there is some inherent flaw with the block transaction, but I would like to understand why it is not working. It is simply a slow scheduled transaction and I can perhaps use a trigger as well which may clean this up, but right now for testing, there is no trigger. I am trying to write the history of a fifo array from a parts/inspection tracking data file (an array of UDTs that are themselves string/int/real arrays) created in the PLC.

Thanks!

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**Author:** ![19tb21](https://avatars.discourse-cdn.com/v4/letter/1/0ea827/32.png) [@19tb21](https://forum.inductiveautomation.com/u/19tb21)\
**Post date:** [May 24, 2019, 4:19am UTC](https://forum.inductiveautomation.com/t/block-transaction-group-duplicates-even-when-rows-do-not-change/25253/2 "2019-05-24T04:19:05Z")

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Cleaned up the handshake with PLC, and am using a proper trigger now, but I still have the same behavior. Rows do not change and yet it will write new rows of data of variable size. To clarify, the information in the FIFO record has not changed, and the transaction group is acting as though it has changed. It is odd that it writes a different number of rows each execution – the block added is different each execution (and of course I am under the impression it should not be executing at all).