# Timediff SQL Ignition **URL:** \ **Category:** Ignition\ **Created:** [September 21, 2020, 6:10pm UTC](https://forum.inductiveautomation.com/t/timediff-sql-ignition/38899 "2020-09-21T18:10:28Z")\ **Posts on this page:** 2\ **Page:** 1
**Author:** ![DD\_Chelsea](https://avatars.discourse-cdn.com/v4/letter/d/b9e5f3/32.png) [@DD\_Chelsea](https://forum.inductiveautomation.com/u/DD_Chelsea)\ **Post date:** [September 21, 2020, 6:10pm UTC](https://forum.inductiveautomation.com/t/timediff-sql-ignition/38899/1 "2020-09-21T18:10:28Z")
Hello, good afternoon everyone. I’m actually working on a parts management system and i have a doubt about how to update a column: The column **fecha** is the date when the call was initiated. I need to update every 5 minutes the timediff between the column fecha and the actual time and write it on the timediff column for every row. ![image](https://us1.discourse-cdn.com/inductiveautomation/original/3X/1/a/1aeeb41b3a2290439b0274a4f60abb1c1eeb760c.png) Do you know a way to perform this update on SQL in Ignition? Thanks in advance for your time and help. Regards. ---
**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:** [September 21, 2020, 9:31pm UTC](https://forum.inductiveautomation.com/t/timediff-sql-ignition/38899/2 "2020-09-21T21:31:40Z")
The timediff column should be a derived column rather than an actual column in your table. If you want to capture historically how long it took, then you cshould have a column that stores the DateTime the process finished as well. Have a look at these for time diff from now though [https://www.w3schools.com/sql/func\_sqlserver\_datediff.asp](https://www.w3schools.com/sql/func_sqlserver_datediff.asp) [https://www.w3schools.com/sql/func\_sqlserver\_getdate.asp](https://www.w3schools.com/sql/func_sqlserver_getdate.asp) These apply for Ms sql as you didn’t specify a sql server