Check database for item and create it if it doesn't exist
You don't need the empty if branches. An if without an else automatically returns unit. So you can simplify it to:

let saveTag question = 

    if question.Tag &lt;&gt; null then
        let tagCount = 
            query{
                for row in db.Tags_Tags_Tags do
                where (row.Tag = question.Tag)
                select row
                count
            } 

        if tagCount = 0 then
            let tagToSave = 
                dbSchema.ServiceTypes.Tags_Tags_Tags(
                    Tag = question.Tag
                )
            insertRowIn db.Tags_Tags_Tags tagToSave
            saveToDb()