I upgraded SharePoint 2010 Farm using database attach method to SharePoint 2013. I have many site collections with their own databases. Overnight randomly one site collection database becomes huge from few MB to 70 GB or more on the sql Server. It is giving warning disk space is too low. I see one of the database and its log file have swelled very big more than 70 GB. If I go to the site collection corresponding to that database I don't see any content there all list and document libraries have same content. I don't know where to look for. I am not very good in sql Server. Any help will be appreciated. Thanks.
When we installed SharePoint 2013, we confused with Minimum Software requirements. For maximum we put the latest and greatest Software. In Minimum Requirements (Minimum Requirements ) there is Sql Server 2012. We used Sql Server 2017. This one caused the problem. Please read the software Requirements carefully. There is no Maximum Requirements. Only Minimum Requirements are tested and work. We changed Sql Server 2017 back to Sql Server 2012 and now everything is working fine. Thanks.