I got some legacy applications of work. One of them needed a new feature for something. Including database update scripts. So it was changed, very carefull beca

I got some legacy applications of work. One of them needed a new feature for something. Including database update scripts. So it was changed, very carefull because it had to use a database trigger ( ms sql) which i haven't used before. It was released in demo/test environment, for 1-2 months and there was never an error. When it got deployed into production, the integrating applications with it went to shit. Rollbacked everything and it was fine again. Made me seriously doubt myselve. I contacted the older devs that touched parts of the database and application, they didn't saw any issues. Fast forward 2 months, i heard it was deployed again into production without any issues. 1 month afterwards, a colleague found an "issue" with the deployments. In short: if you deploy to production, for some applications it would deploy and older version ( 50% chance since a swap happened). Urgh