postgresql - Typecheck SQL query -

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Is there a relational database that can output the return type of a query before it runs? As an example, GIVE_TYPES is selected from a question like GIFE_TYPES name, age of person without actually having to query VARCHAR (255), Integer if it is a If this is not the case, then why is this the case?

Edit The first comment made me realize that I have to issue a little more complicated use. Imagine if the query was something like this: 

  select parent_name, COUNT (name) by parent group by parent_name;

In order to select the names of all parents and the number of children to them, I expect something like this as the result for VARCHAR (255), Integer , But a column inspection will not tell me about the return type of COUNT .

The calculation return type is always int


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