How to Resolve 'View's SELECT contains a subquery in the FROM clause' in MySQL?

Subquery in View's FROM Clause Troubleshooting

The error "View's SELECT contains a subquery in the FROM clause" occurs when a MySQL view's SELECT statement includes a subquery within the FROM clause. As per MySQL documentation, this is not allowed.

To address this issue in your query to create a view named view_credit_status, consider the following solution:

The problematic subquery is:

(select credit_usage.client_id, 
        sum(credits_used) as credits_used 
 from credit_usage 
 group by credit_usage.client_id) as t0

Create a separate view for this subquery:

create view view_credit_usage_summary as 
select credit_usage.client_id, 
       sum(credits_used) as credits_used 
from credit_usage 
group by credit_usage.client_id

In the view_credit_status view, reference the new view_credit_usage_summary view instead of the subquery:

create view view_credit_status as 
(select credit_orders.client_id, 
        sum(credit_orders.number_of_credits) as purchased, 
        ifnull(view_credit_usage_summary.credits_used,0) as used 
 from credit_orders
 left outer join view_credit_usage_summary on view_credit_usage_summary.client_id = credit_orders.client_id
 where credit_orders.payment_status='Paid'
 group by credit_orders.client_id)

This approach separates the subquery into a dedicated view, allowing you to access its results without violating MySQL's restrictions.

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