Create Virtual Column in mysql -

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i have mysql query this:

$statement=$pdo->prepare("select id activity_id,type,status,description, (select sum(price*worked_hours) tbl_working_hours  id_act = activity_id) total_hours tbl_activity");

there 2 tables:

1- tbl_activity

2- tbl_working_hours

i trying create virtual column each row based on summary table.

thanks

you might want use subqueries

select [...], (select count(*) mytable) count myothertable

thats solution comming mind. problem way pretty costly when comes performance.


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