subquery method
Sub-query select statement also select both
Then sqlarchemy in order to achieve a sub-query requires the following steps
1. subquery query code written in a conventional manner, and then later execute a method subquery query object, a query into subqueries.
2. In the sub-query, the field will later need to use the name taken by individual lable method.
3. in the parent query, if you want to use the field sub-query, then returns "" c "on the value of the sub-queries can be" property to get c = Column
Example:
