MySQL: view with subquery in the from clause limit

problem ：

In MySQL 5.0 why does the following error occur when trying to create a view with a subquery in the FROM clause? stay MySQL 5.0 in , Why try in FROM The following error occurs when creating a view with subqueries in Clause ？

ERROR 1349 (HY000): View's SELECT contains a subquery in the FROM clause error 1349 (HY000)： View's SELECT stay FROM Clause contains subqueries

If this is a limitation of the MySQL engine, then why haven't they implemented this feature yet? If this is MySQL Engine limitations , Then why haven't they implemented this function yet ？

Also, what are some good workarounds for this limitation? in addition , What are the good solutions to this limitation ？

Are there any workarounds that work for any subquery in the FROM clause or are there some queries that can not be expressed without using a subquery in the FROM clause? Is there any solution for FROM Any subquery in Clause , Or whether there are some queries that are not used FROM Clause cannot express ？

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An example query (was buried in a comment): An example query （ Buried in comments ）：

SELECT temp.UserName FROM (SELECT u1.name as UserName, COUNT(m1.UserFromId) as SentCount       FROM Message m1, User u1       WHERE u1.uid = m1.UserFromId       Group BY u1.name HAVING SentCount > 3 ) as temp

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Solution ：

Reference resources ： https://stackoom.com/en/question/rba