Something that used to plague me is that I had database processes importing Excel docs from clients, and if the first few rows in a column were numbers, SQLServ

Something that used to plague me is that I had database processes importing Excel docs from clients, and if the first few rows in a column were numbers, SQLServer assumed that all the values must be numbers. Then it would run into cells containing other strings, and instead of revising its assumption, it would just import them as null. Since clients often didn't have great data hygiene, it was a problem. I finally solved it by exporting to csv, and using third-party software that handled its own import and did it correctly.