OA system through the pit of department management positions

1. Why is the output of all queries after all jobs are null?

A: (1) the first is certainly no walk in to the database so the output should be null inside view xml sql statement and note the statement id resultType or resultMap (to see the return of this table do) then this is very important the sql statement

2. Form form must correspond to the preceding page on submit

3. garbled on the browser because you're not a modified within the page  

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