# Monitor a SQL Response Table for Change

**URL:** <https://forum.inductiveautomation.com/t/monitor-a-sql-response-table-for-change/18171>\
**Category:** Ignition\
**Created:** [May 25, 2018, 3:01pm UTC](https://forum.inductiveautomation.com/t/monitor-a-sql-response-table-for-change/18171 "2018-05-25T15:01:17Z")\
**Posts on this page:** 1\
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**Author:** ![AlThePal](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/althepal/32/3603_2.png) [@AlThePal](https://forum.inductiveautomation.com/u/AlThePal)\
**Post date:** [May 25, 2018, 6:24pm UTC](https://forum.inductiveautomation.com/t/monitor-a-sql-response-table-for-change/18171/2 "2018-05-25T18:24:03Z")

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In a loosely-coupled system like this, I don’t think you have an alternative to setting a value and polling for a response. In any case polling a database works perfectly well unless you need a response time in the milliseconds range.

I would put this is in a gateway Tag Change script. On the PLC trigger issue your write, then enter a loop and poll for a response, timing out if it takes too long. When you pause, remember to use something like `system.util.invokeLater()` as per [this post](http://forum.inductiveautomation.com/t/time-sleep-function-in-ignition/10337).

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