mysql - insert into department_new select a.*,null from departments a;" what does select a.* means -


i trying insert data 1 table in mysql, understand below query

insert department_new select a.*,null departments a;

what select a.* means , how insert values correctly new table,

kindly help

a alias table departments

and a.* means column same departments.*

so complete statement

insert department_new select a.*,null departments a;

means, values table departments should stored table department_new plus new column null should inserted.

it works fine, if order in both tables equals. in form there risk, copy values wrong column.


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