mysql - Possible positions and executing order about aggregation functions in select statement in sql? -



mysql - Possible positions and executing order about aggregation functions in select statement in sql? -

where can set aggregation functions in 1 sql query (in select clause, in having clause or others ). , what's executing order of aggregation functions in logical processing order of select statement?

the post "order of execution of query" there doesn't cover functions' executing order.

1) can set subquery after ,from , middle of sql statement.

//after select * orders order_id in (select oreder_id orderconfirmed) // after select * (select * table) //middle of sql statement select id,(select id table1) form table2 2) can set aggregation function in both select clause , having clause. //in select select count(employee) employees grouping employee_dept //in having select count(employee) employees grouping employee_dept having(max(salary)>2000) 3) order of execution of sql statement 1)from 2)where 3)group 4)having 5)aggregate function 6)select

mysql sql-server sql-function

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