mysql - Error : <table_name> specified twice, both as a target for 'UPDATE' and as a separate source for data -


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i want update tot_sales attribute tot_sales sum of order_price's of orders handled salesman

i wrote update query. gives error

#1093 - table 'salesman' specified twice, both target 'update' , >as separate source data

update salesman set salesman.tot_sales = (select sum(orders.order_price)                           orders                           inner join salesman on orders.emp_id = salesman.emp_id                           group salesman.emp_id                           )

using approach, use correlated subquery rather aggregation:

update salesman s     set s.tot_sales = (select sum(o.order_price)                        orders o                        o.emp_id = s.emp_id                       );

this written as:

update salesman s left join        (select o.emp_id, sum(o.order_price) total_price         orders o         group o.emp_id        ) o        on o.emp_id = s.emp_id     set s.tot_sales = o.total_price;

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