Identify the last instance using join in SQL Server
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I have three tables: File, Word and WordInstance:

    File: FileId, FileName
    Word: WordId, WordName, FileId (latest file containing this word)
    WordInstance: WordInstanceId, WordId, FileId. (this table contains all instance of file/word relationship)

Now, given a FileId, I want to return a flag of whether there are other files that having all the words for the given file. 